[Relevant documents: Ninth Report from the Defence Committee, Session 2006-07, on The Future of the UK's Strategic Nuclear Deterrent: the White Paper, HC 225-I, and the Government's interim response thereto, available in the Vote Office. Fourth Report from the Defence Committee, Session 2006-07, on the Future of the UK's Strategic Nuclear Deterrent: the Manufacturing and Skills Base, HC 59, and the Government's response thereto, HC 304 (Session 2006-07). Eighth Report from the Defence Committee, Session 2005-06, on the Future of the UK's Strategic Nuclear Deterrent: the Strategic Context, HC 986, and the Government's response thereto, HC 1558 (Session 2005-06).]

We come now to the main business. It will be helpful to the House to know that all Back Benchers will be limited to eight minutes. Because of the high number of applications made by hon. Members on both sides of the House, it is not a day to approach the Chair to ask whether they will be called. I inform the House that I have selected the amendment in the name of Jon Trickett.

I beg to move,

That this House
supports the Government's decisions, as set out in the White Paper The Future of the United Kingdom's Nuclear Deterrent (Cm 6994), to take the steps necessary to maintain the UK's minimum strategic nuclear deterrent beyond the life of the existing system and to take further steps towards meeting the UK's disarmament responsibilities under Article VI of the Non-Proliferation Treaty.

I must at once declare a potential interest, in that the propulsion system for the existing submarines is manufactured in my constituency.

Let me set out the nature of the decisions that the House is being asked to support today. They are whether or not to take the steps necessary to maintain a minimum strategic nuclear deterrent for the UK—a single system comprising submarines, missiles and warheads—and to take further steps towards meeting our disarmament responsibilities under article VI of the non-proliferation treaty.

Specifically, that will mean a decision to begin a process to design, build and commission submarines to replace the existing Vanguard-class boats. This will necessarily take some 17 years. That is a calculation based on our own experience and that of other allied nuclear weapon states. Moreover, we must also decide whether we will join the American programme to extend to the early 2040s the life of the Trident D5 ballistic missiles which those Vanguard submarines currently carry, and whether we will reduce the number of our operationally available warheads to fewer than 160 by the end of this year.

The United States nuclear posture review that went to Congress in December 2001 estimated that it would take 13 years, not 17 years, to replace a US Trident submarine.

The United States submarines are different from our own. They are differently designed, they have a different design life and so on. That may have been the conclusion of American work; it is not the conclusion of the work that has been done in this country.

Does the Secretary of State accept that all these issues must be subject to review over the years, and that many of us who will support her today reserve the right to review our positions when the warheads are considered in the next Parliament?

As my hon. Friend is aware, we are not making any decision about the warheads in this Parliament, so the matter will inevitably come before a subsequent Parliament.

The decisions that we are asked to make today are serious and weighty, and they are being put before the House following sustained and thorough consideration and debate. Those decisions affect the fundamental security of this country and its people, and they involve significant cost, so it is right that the House should fully debate the Government's proposals and have the final say on the choice that this country makes.

Is the Foreign Secretary saying that we are making a decision today to keep all our options open, or are we making a decision that would commit a future Parliament to large expenditures when we go through the big gateway decision in due course?

My right hon. Friend will know that that question was raised with the Prime Minister a few moments ago and he answered it clearly. It is the decision of principle that we are required to make today. It is inevitable that there will be future discussions, and there will be decisions down the road as the programme proceeds. But that will not be the case unless we make the decision today.

Several hon. Members:

rose—

I shall give way to Mr. Leigh, then I shall make progress.

Does the Secretary of State agree that it is possible to believe in both the independent nuclear deterrent and value for money? There is a distressing tendency for Ministry of Defence projects to go over time and over budget. Will she therefore welcome the assurance given to me by the Comptroller and Auditor General this week that he will carry out an innovative exercise and issue an ongoing assurance report on value for money, to ensure that we get real value for money on the project?

Yes indeed. I welcome that, as will the whole House. We rely on the Committee chaired by the hon. Gentleman to sustain that scrutiny.

Since the non-proliferation treaty came into force in 1970, all nuclear weapons states have taken steps to maintain their deterrents. The decisions on which we are seeking agreement today are no different. But the UK has been more open and transparent than any other state in explaining the basis of our decisions in advance to our people and to the international community.

There are four key issues. I will address each in turn. The first is what are we doing to fulfil our obligations under the nuclear non-proliferation treaty. The second is whether it is still in the national interest to maintain a nuclear deterrent. The third is why such a deterrent should be in the form that we now propose. The final issue is why we need to make this decision now.

The NPT created two distinct categories of states. Those that had already conducted nuclear tests—ourselves, the US, the Soviet Union, China and France—were designated nuclear weapons states and could legally possess nuclear weapons. All other states-signatory were designated non-nuclear weapons states. Article VI of the NPT imposes an obligation on all states

"to pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament, and on a Treaty on general and complete disarmament".

The NPT review conference held in 2000 agreed, by consensus, 13 practical steps towards nuclear disarmament. The UK remains committed to these steps and is making progress on them.

We have been disarming. Since the cold war ended, we have withdrawn and dismantled our tactical maritime and airborne nuclear capabilities. We have terminated our nuclear capable Lance missiles and artillery. We have the smallest nuclear capability of any recognised nuclear weapon state, accounting for less than 1 per cent. of the global inventory, and we are the only nuclear weapon state that relies on a single nuclear system. The Prime Minister has announced a further unilateral reduction in our nuclear weapons in line with our commitment to maintain only the minimum necessary deterrent. We will reduce the stockpile of operationally available warheads by another 20 per cent., to fewer than 160 warheads during the course of this year. This will involve the eventual dismantlement and disposal of about 40 warheads. The UK will then have cut the explosive power of its nuclear weapons by three quarters since the end of the cold war. That is more than any other nuclear weapon state has yet done.

I want to be clear about the point that my right hon. Friend is making in comparison with her answers to earlier interventions. Is she saying that today's decision is a reduction of 20 per cent., or is she saying, as I thought she was, that during the 2012 to 2014 window there will be a decision that can be made by this House to determine whether the 20 per cent. reduction could be increased to, say, 50 per cent.?

That depends, of course, on whether the House votes for this motion. If it does, we are committing ourselves to making that reduction by the end of this year. I hope that that is a reassurance to my hon. Friend. [ Interruption. ] There is no need for a window; the window runs to the end of this year. If the motion is carried today, we are committing ourselves to that further 20 per cent. reduction in warheads.

Obviously, as the Foreign Secretary rightly said, we are not the biggest player among the nuclear arms powers—and, yes, there have been steps to disarmament. Why, however, would the Government's position, which is in principle to retain the nuclear deterrent, be a better trigger for disarmament in the 2010 talks than a decision to defer on the basis of reduction now and prospective reduction or abolition of nuclear arms later?

Let me first say to the hon. Gentleman that, as I have already pointed out, we have been disarming over the course of the past 10 years, with singularly little response. There is therefore no evidence whatever for the notion that if we defer this decision, that will somehow magically produce a different response from other players than we have had hitherto. I simply say to him—I apologise if I am offending anybody in the House in saying it—that there are only two credible positions to take today: you are either in favour of this decision or you are against it. The notion that there is an excuse that allows people to get out of the problem today and return to it later is, frankly, escapology.

Before my right hon. Friend moves away from the issue of proliferation, can she give the House an assurance that if we vote for the Government's motion today, there will be renewed efforts to secure the measures on nuclear weapons disarmament mentioned in article VI of the non-proliferation treaty, particularly to try to get India, Pakistan and the other non-signatories to the NPT into the global nuclear arms control system?

I can certainly give my hon. Friend that assurance without any difficulty. The next step that we hope to take is to bring forward negotiations on the fissile material cut-off treaty. He is also absolutely right that it is extremely important to work with other states that are known to have a nuclear weapons capacity and have not come within the ambit of moving towards disarmament. We will certainly continue such work.

Does my right hon. Friend agree that for the nuclear non-proliferation treaty to be effective, two things are important: first, it has to be enforced; and secondly, non-nuclear states have to be convinced of the logic of it? If someone was in Israel at the moment considering whether to get rid of the nuclear weapons that they have, or if someone was in Iran—I mean a secular Iranian, not Ahmadinejad—wondering whether it is a good idea to acquire nuclear weapons, would it really be logical for them to think that they should not acquire nuclear weapons if the message they get from this country is that we need to prepare for producing the next generation just as an insurance policy for things that we do not know are going to happen?

I will come to that point later in my remarks. I would simply say to my hon. Friend that that is the most dangerous argument of all. It does nothing. Those who want to see nuclear disarmament, and those who are anxious and nervous about the decision that the House is being asked to make today, are doing nobody any service by encouraging the notion that any decision that we make gives an excuse to others, who are, in the case of Iran, signatories to the nuclear non-proliferation treaty —[ Interruption. ] I hear the words, "He didn't say that." No, but it was quite heavily implied. There is no justification for others in the decision that we are being asked to make.

This debate has come about not because of Trident coming to the end of its shelf life but because the Vanguard-class submarines will need to be replaced. Could the Secretary of State clarify how much it will cost to decommission the four submarines and what budget that will come from?

I cannot, offhand, but I am sure that my right hon. Friend the Defence Secretary will able to give the hon. Gentleman the figures later on. There are some figures in the White Paper, but I am not carrying them in my head.

The latest proposal does not change the trend of disarmament that we have been pursuing. I want clearly to spell out to the House what we are not doing. We are not upgrading the capability of the system. We are not producing more usable weapons. We are not changing our nuclear posture or doctrine—in particular, we do not possess nuclear weapons for "war fighting" or tactical use on the battlefield. And we have not lowered the threshold for the use of nuclear weapons. Again, I know that there are those who are unhappy with the proposal before the House and who have sought in various ways—outside the House, not just within it—to imply that these are the decisions that the House is being asked to make. They are not. That excuse will not stand.

We have taken other unilateral actions in line with the 13 steps. We have not conducted a nuclear test since 1991. We ceased production of fissile material for use in nuclear weapons in 1995. And all excess fissile material stocks no longer required for defence purposes have been placed under international safeguards. Those unilateral actions have been complemented by active diplomacy on multilateral nuclear disarmament of the kind that my hon. Friend Mike Gapes, who chairs the Foreign Affairs Committee, mentioned in seeking an assurance that we would pursue it. We led international efforts on the comprehensive test ban treaty. The UK ratified the treaty in 1998, and our diplomats continue repeatedly to urge other countries to ratify so that it can enter into force. As I said, we have called repeatedly for the immediate start of negotiations in the conference on disarmament in Geneva on a fissile material cut-off treaty.

If what the Foreign Secretary says is internationally accepted, why does Mohamed el-Baradei so fundamentally disagree with her on the impact that it will have on proliferation?

I appreciate that Dr. el-Baradei has of late made a number of remarks about his wish that Governments—nuclear-armed states—should not pursue such measures. However, he knows, as we know, that all nuclear-armed states have indeed taken steps to modernise and keep up to date the weapons and facilities that they have. That is exactly the decision that the United Kingdom is making, no more and no less. I must say to the hon. Gentleman that I have looked to see whether I can discover Dr. el-Baradei making similar comments when other nuclear weapon states made those choices; so far I have not been able to unearth such comments.

Could the Secretary of State give those of us who desperately want multilateral disarmament to succeed an idea of what the chances are for other nuclear states to match our unilateral action in getting rid of all battlefield and tactical weapons?

I cannot speculate on those chances, but these are steps that we thought that it was right to take. We continue to urge them on others, and we will continue to do so through the conference on disarmament. I share the view of many in the House that it is perhaps time for a fresh push on these measures on the international stage. How successful such a push would be remains to be seen, but there have been a series of bilateral agreements since the end of the cold war, which have greatly reduced the major nuclear arsenals. By the end of this year, the United States will have fewer than half the number of silo-based nuclear missiles that it had in 1990. By 2012, US operationally deployed strategic nuclear warheads will be reduced to about one third of 2001 levels. Under the terms of the strategic offensive reductions treaty, Russia is making parallel cuts, and the French have withdrawn four complete weapons systems.

Britain remains committed to the abolition of nuclear weapons, and we are actively engaged, and encouraging others to be engaged, in a process that will lead to that goal. But progress will be steady and incremental, and only towards the end of that process will it be helpful and useful for us to include our own small fraction of the global stockpile in treaty-based reductions.

So there is no basis to suggest that we have done anything other than fully comply with our obligations under the NPT. Indeed—I say this to the House with some respect—I regard it as dangerous folly to equate our own record, as some have tried to do, with that of countries such as North Korea and Iran, which have stood or stand in clear breach of their obligations as non-nuclear weapon states under the NPT. There is no legal or moral equivalence between their position and ours. I would urge people, whatever other arguments they might use to oppose the motion, not to use that one, because it undermines the very basis of the treaty itself: that those recognised as non-nuclear weapon states should not seek to acquire nuclear weapons. The international non-proliferation regime is not perfect, but it has prevented the wide-scale proliferation of nuclear weapons. I regard it as dangerously irresponsible to use the excuse that the UK is retaining its weapons to justify others seeking to acquire them, and it runs the real risk of increasing the global nuclear threat, not reducing it.

Does the Secretary of State not think that it might be dangerous folly to use the expression "nuclear deterrent" in this context? Does she accept that these proposals are hardly going to deter Iran and North Korea? Will she explain her policy in the context of its deterring those two countries from continuing with their plans?

We are working on deterring Iran and North Korea from pursuing their present course of action by other, diplomatic, means, as I hope the House would want. I sincerely hope that everyone in the House wants those negotiations to succeed, and wants North Korea and Iran to be deterred from continuing on their present course of action. I really hope that people will not use arguments that suggest that they have every cause to continue.

That brings me to the second of the four pivotal questions. Why does this country need to retain its nuclear weapons? I am inclined to turn the question on its head and ask instead whether this is the time for us to abandon our nuclear deterrent, or to deny future Governments and Parliaments the ability to maintain it. It is true that the cold war has ended. Actually, it had ended before the existing deterrent came into service, as it had been ordered some years before. It is also true that, as of today, we do not identify an enemy with both a nuclear capability and the ability and intent to use it against our vital interests.

However, significant nuclear capabilities and nuclear risks remain. There are still substantial nuclear arsenals; the number of nuclear-armed states has increased, not decreased; and there is a significant risk of new nuclear-armed states emerging. Moreover, several of the countries that either have nuclear weapons or are trying to acquire them are in regions that suffer from serious instability or are subject to significant regional tension. So, there is the potential for a new nuclear threat to emerge or re-emerge.

The Foreign Secretary is absolutely right to say that this is not the time to be giving up our national nuclear deterrent. Does she agree, however, that it is the right time to look at future non-nuclear national deterrents such as hypersonic mass technology, which would give us greater flexibility in enforcing our foreign policy without any nuclear fallout? Has any consideration been given to hypersonic mass technology?

If the hon. Gentleman will forgive me, I do not intend to get drawn down the path of discussing other technologies. We have quite enough to do in dealing with the one that we have in the course of this debate.

The Secretary of State will know that our nuclear weapons have been pointing at nobody since 1994. Does she not recognise that the immediate, and perhaps medium-term, threat comes from those countries that are developing biological and chemical weapons? Does she not think that the money spent on upgrading and renewing our nuclear weapons system would be better spent on dealing with that particular threat, or on ensuring that our troops in Afghanistan were properly equipped with what they need?

I shall come to the proportion of the costs in a few moments. I do not think that the two issues that the hon. Gentleman has raised are mutually incompatible. It is necessary, as he says, to consider the range of threats that this country faces, and the Government are doing that. This is one of them, and we believe that it would be irresponsible of us to ignore it.

Will the Foreign Secretary give way?

If my hon. Friend will forgive me, I must make some progress.

The time scale we must address is not just the next 10 or 15 years, and it does not involve current or recent developments. We are talking about maintaining our ability to keep a minimum independent nuclear deterrent after 2024. To decide not to retain that ability would require us to be confident that, in the next 20 to 50 years, no country with a current nuclear capability would change its intentions towards us and that no power hostile to our vital national interests and in possession of nuclear weapons would emerge. I sincerely regret that I cannot advise either the House or the British people that I believe such confidence would be justified, or that we should remove from future Parliaments the ability to maintain our deterrent.

Given that all three major parties in the House stood at the last election on a platform of maintaining Trident, does my right hon. Friend agree that it would be wrong for us to make a decision today that would prevent the British people from electing a Government at the next election who would either retain or get rid of Trident, by pre-empting such a decision by voting against the Government motion?

My hon. Friend makes an extremely powerful point, and he makes it well. It is indeed the case that the decision of principle that we are being asked to make today could set the course for future Parliaments if we were to reject the motion before the House.

I thank the Foreign Secretary for giving way. She will recall that, in the past, our party and others have campaigned against nuclear weapons and for disarmament. She has made much of the adherence to the non-proliferation treaty, but is it not the case that the message going around the world is that a vastly enhanced delivery system—achieved through a new generation of submarines—will be contrary to the whole spirit of the treaty and likely to encourage proliferation rather than reduce it?

I am sorry to have to say this to my hon. Friend, but that is complete and utter rubbish. We are not here to make a decision about a vastly enhanced system. I must also say to him in all seriousness that if he wants to encourage the idea that we should pursue non-proliferation, it is very unwise to keep arguing that other people are perfectly justified, because of what we are doing, in pursuing further nuclear weapons. I understand and respect the strength of his convictions, but I really think that it is time for people who share those convictions to make up their minds whether they are or are not trying to encourage other states to develop nuclear weapons.

In light of the possible changed threats to this country, does my right hon. Friend agree that whether one lives in Hemsworth, Southampton, Derby or Wolverhampton, it is difficult to pop out to the local supermarket and buy a nuclear submarine as a delivery system? If we delay the decision, however, we might be in that position in the future.

My hon. Friend is entirely right. Some who have commented on these issues have perhaps been misled—this brings me back to my point about the transparency with which the Government have pursued the issue—because in the past the conceptual and design stages have often been pursued behind closed doors. The matter has not been made known to Parliament, and decisions have not been sought from Parliament before continuing such a programme. The programme needs to be pursued for a sustained period of years, and that is the principal reason that the decision must be made today.

Will the Foreign Secretary give way?

No, I must get on.

The deterrent is not an alternative to diplomacy. We will keep pushing for multilateral disarmament, keep working through the United Nations to prevent proliferation of nuclear weapons, and keep encouraging nuclear weapon-free zones, including in the middle east. The wider goal of our diplomacy remains to prevent and resolve all conflict by reducing regional tensions—not least between the Palestinians and Israel—by promoting economic development, and by dealing with underlying insecurities such as an unstable climate and the illegal trade in arms. All of that work will continue.

The third issue lies in the details of the proposals. After thorough and exhaustive analysis, the Government are confident that a submarine system with ballistic missiles remains the most effective and least vulnerable form of deterrent. From that stems the decision to extend the life of the D5 missile. Simply put, it makes no sense to invest in submarines built around the D5 missile unless we have assurance that such a missile will be available after 2024.

The White Paper makes it clear that we will look hard at whether it is possible to maintain our policy of continuous deterrent patrolling with three boats rather than four through improvements in the technology, operational procedures and maintenance schedule of the new class of submarines. However, we will not take irresponsible risks with our capability, as we rely—unlike others—on a single, minimum system.

The judgment that we will need to maintain an operational stockpile of fewer than 160 warheads is based on a professional analysis of the minimum that is required to deter. That analysis does not, in our view, support any of the alternative proposals including those made by the Liberal Democrat party for a reduction to just 100 operational warheads. The claim is made that those proposals are based on expert analysis, but nothing whatever has been done to explain either who the experts were or what the analysis was. We do not believe that such a number would leave us with a credible and effective nuclear deterrent.

Our estimate is that the costs of operating and maintaining our deterrent between 2020 and 2050 will be equivalent to some 5 or 6 per cent. of the current defence budget—similar to the cost of our current deterrent. The procurement cost of the new submarines and associated equipment and infrastructure will be in the region of £15 billion to £20 billion for a four-boat fleet. Those costs would fall principally between 2012 and 2027. We estimate that the procurement costs are likely on average to be the equivalent of about 3 per cent. of the current defence budget over the main period of expenditure—roughly the same as for the Trident programme. That investment will not come at the expense of the conventional capabilities that our armed forces need.

My right hon. Friend has already pointed to the difficulties of delaying a decision on Trident. Does she agree that sourcing the technical capacity to support the existing nuclear provision is a fundamental difficulty and that we need to send a clear signal, both to the academic institutions of this country and the companies that will be involved in the provision of Trident, that we intend to make a commitment, so that they can begin to prepare for that and ensure that we have the expertise to secure our nuclear capacity, both militarily and domestically?

My hon. Friend is entirely right and, if I may say so, displays her engineering expertise and understanding of how the industry works. The decision to be made by the House is not on anything other than the political, strategic and security needs of the country. However, it is also necessary to take into account the industrial implications, and those implications certainly reinforce rather than weaken the case for making a decision now.

If the costs described by my right hon. Friend were exceeded—defence projects have a track record of exceeding their budgets—will she also guarantee that those excess costs would not impact elsewhere in the defence budget?

The whole purpose of the scrutiny to which Mr. Leigh, who chairs the Public Accounts Committee, referred is to make sure that that is not the case. I think that my hon. Friend will find a reference in the White Paper to the costs of the existing system, which, in real terms, are pretty close to identical to the likely costs of the new system. The kind of overrun that he describes has not been the case with that programme.

The Government have a strong record on defence spending. The last spending review increased the defence budget by an average of some 1.4 per cent. a year in real terms. The defence budget for 2007-08 will be some £3.7 billion higher than in 2004-05, and we have kept the proportion of GDP spend on defence pretty steady since 1997 at around 2.5 per cent. That is our understanding and expectation of the level of costs.

Will the Foreign Secretary give way?

No, I must get on. I have been speaking for more than half an hour.

The final question is, why must we make a decision now? Some have suggested that the decision can be delayed. Let us make no mistake—the net result of that would be not to delay the decision, but to run the risk of making it by default. All our advice is that if we do not start the process of designing the new generation of ballistic missile submarines now, it will already be too late.

The Vanguard submarines are due to start to reach the end of their planned lives from 2017 onwards. We are advised that we can—and so, in consequence, we will— extend their life by up to five years. Extending beyond that period would be risky. Let us not forget that submarines comprise our only nuclear weapons system. Some have drawn comparisons, as was done today, with the United States, but its Ohio boats are not the same as our Vanguards—they had a longer design life and have major engineering differences. We must therefore work on the basis that the first of our existing submarines will have to go out of service in 2022, and the second in 2024. By the time that the second goes out of service, we will need to have a fully operational replacement if we are to maintain continuous patrolling.

Our best estimate, also tested against American and French experience, is that the process of designing, manufacturing, testing and deploying a new class of submarines takes about 17 years, which takes us to 2024. That is why we must make a decision now.

The Foreign Secretary has indicated that we must make a decision now to begin the design process for the new submarines. She has also indicated that further decisions, which we are not making today, will have to be made about ordering the submarines, renewing or replacing the warheads or ordering successors to the D5 missile. In reply to my hon. Friend Dr. Whitehead, she indicated that future Governments and Parliaments will have to

"discuss the most appropriate form of Parliamentary scrutiny" for those decisions. If this Government are still in power when those decisions come to be made, will she indicate whether she believes the most appropriate form of parliamentary scrutiny to be further votes and debates in Parliament on those matters?

I understand entirely my hon. Friend's point, but he knows that I am a former Leader of the House. No one is less likely to be prepared to commit future Governments and Parliaments to a certain course than a former Leader of the House. I simply draw his attention to the words uttered by my right hon. Friend the Prime Minister and to the clear facts before the House—the decision in principle must be made today, but the decision on the warheads, for example, will not come in this Parliament. It would be improper for me to bind a future Government or Parliament, but every party in the House will have heard the questions and points raised, and every party will take account of them. I certainly assure my hon. Friend that this Government will do everything that we can to keep the House fully informed and to make sure that the Select Committee is kept up to date.

Incidentally, I have been reading of late comments that the decision was rushed. We announced in 2003, in the White Paper, that this was the time scale within which it would have to be made. I saw suggestions in The Guardian today that other decisions were being made in secret. In fact, they were announced to the Select Committee in November 2005. I believe it was the late Enoch Powell who said that the best way to keep a secret was to announce it in Parliament. Unfortunately, it is proved daily that that is the case.

Will the Foreign Secretary give way?

I am sorry, but I must get on. I am approaching the end of my speech and many Members wish to contribute.

Some Members have sought assurances on whether this is only a provisional decision, dependent on further decisions down the line. Today's decision does not mean that we are committing ourselves irreversibly to maintaining a nuclear deterrent for the next 50 years, no matter what others do and no matter what happens in the rest of the world. That would be absurd, unnecessary and, indeed, incompatible with the nuclear proliferation treaty. Nevertheless, the strategic case for maintaining the deterrent has been made, and has been laid out perhaps more fully than ever before. It is for the House to decide whether or not it supports that decision of principle. We must make a clear decision that confirms to the British people and the rest of the world that we are not abandoning our deterrent.

Of course, if there were a fundamental change for the better in the strategic environment—in particular, massive significant progress on non-proliferation and disarmament—it would obviously be right for future Governments to look at the issue again, and inevitably they would. As I have said, further decisions will in any case be needed on the precise design of the submarines, on whether we need four or three, on whether to renew or replace the warhead, and on whether to participate in any American programme to develop a successor to the D5 missile. It will fall to future Governments and Parliaments to discuss the most appropriate form of scrutiny for those decisions. As I have said, this Government will ensure that there are regular reports to Parliament as the programme proceeds, and we will give the Select Committee our full co-operation as it maintains its regular scrutiny of these issues.

Will my right hon. Friend give way?

I will give way to my right hon. Friend, but he must be absolutely the last.

I am grateful to my right hon. Friend. On the question of parliamentary scrutiny, I understand that she cannot bind future Parliaments. I noted that the Secretary of State for Environment, Food and Rural Affairs announced yesterday that the Climate Change Bill would bind future Parliaments, but I understand that my right hon. Friend is reluctant to do the same. However, will she at least express the opinion to this Parliament that it would be desirable and appropriate for it to be able to take a view at some point in the future—perhaps around the time that the main contracts are let—on whether international circumstances still require us to maintain an independent nuclear missile system?

I do not want to add anything to the words that either my right hon. Friend the Prime Minister or I have already uttered to my right hon. Friend, but I will say to him that I am not sure whether we are at cross purposes. The stage to which he refers is not likely to be reached during the present Parliament. With the deepest respect to my good and right hon. Friend the Secretary of State for the Environment, Food and Rural Affairs, who is a very fine Minister indeed, he has not of course been Leader of the House. [Laughter.] Yet.

I have made the Government's case. There are opponents of that case who believe that nuclear weapons are morally wrong, pure and simple. For the reasons that I have given today, while I respect and understand that stance I must say—as a member of a Government charged, above all, with the protection of the people of this country—that it is not my position. Moreover, those whom that stance leads to oppose this decision should, by that yardstick, have opposed all previous nuclear procurements. Some, I know, have; some, I suspect, have not.

To others, Trident is just a waste of money. In one sense, I hope to God they are right. Nothing would please me or the Government more than to have a nuclear deterrent that was never used, and whose use was never even threatened, because a nuclear threat never emerged. But on the facts before us, we—and they—cannot know that to be true or certain, at least for the next 50 years. While such a risk exists, the Government believe that maintaining a minimum nuclear deterrent remains a premium worth paying on an insurance policy for our nation.

I commend the motion to the House.

The Foreign Secretary has made a very powerful speech, and an extremely good case. It was all the more powerful coming from her, in a way, because she was a long-standing member of the Campaign for Nuclear Disarmament—she once spoke of remaining a member of it even if she became Prime Minister—and she is said to have attended the recent Cabinet meeting to discuss these matters and make the decision that she has just explained with deep reluctance. The fact that someone with her long-held views has reached the clear conclusion—in Government, and with all the information available to her—that the British nuclear deterrent must be retained, updated and replaced is in itself an indication of the powerful case for doing so.

The Foreign Secretary has overcome her reservations; others will wish to voice theirs and to ask many serious questions during the debate, but the arguments for the Government's position are very, very strong. My right hon. Friend the Leader of the Opposition has always made clear that we will support the Government when we believe them to be right. Let me make it clear, therefore, that given our view of the national interest, the Opposition will unite with Ministers in the Lobby tonight.

It is an interesting theory that the Foreign Secretary changed her mind when information became available, but I think the right hon. Gentleman should bear in mind the fact that she changed her mind before she was in Government and before that information was available to her.

I am just very pleased that she changed her mind. I do not want to go into all the arguments about the particular week in which she did so; I am sure she can explain that to us herself.

There are, of course, important questions about costs, timings, the necessary skills base and the lifespan of some of the equipment involved. I shall turn to those shortly, and perhaps the Secretary of State for Defence will comment on them when he winds up the debate. However, we will support the Government's motion, although the phrase

"take the steps necessary to maintain... the existing system" barely does justice to what is being decided: the building of an entire new class of ballistic missile submarines, along with the updating of our Trident missile force, together representing the single most important and expensive procurement of the coming decades. In effect—unless there is, as the Foreign Secretary said, some fundamental and utterly unexpected change in world affairs—this means deciding to replace our nuclear deterrent for another generation, and our vote tonight will be the decision on whether to do so.

The motion also refers to taking

"further steps towards meeting the United Kingdom's disarmament responsibilities under... the Non-Proliferation Treaty".

Let me make it clear that those disarmament steps have the strong support of the Opposition. Britain is already unique among the recognised nuclear weapons states, in that we have reduced our nuclear deterrent capability to a single system, Trident. We have reduced the size of our nuclear arsenal by 70 per cent. since the cold war, and the Government rightly propose to make a further reduction in our stock of warheads from 200 to 160. We have only a single Trident submarine on deterrent patrol at any one time, with its missiles de-targeted.

If my right hon. Friend were Foreign Secretary now, what additional steps would he take to try to achieve more multilateral disarmament on the back of our unilateral moves?

I think there is a very strong case for an intensified effort by this country and our allies to strengthen the non-proliferation treaty. I shall say more about that at the end of my speech, and I shall deal with my right hon. Friend's point then.

For all the reasons I have given, I agree with the Government that their proposals do not breach article 6 of the non-proliferation treaty. That article does not call for unilateral nuclear disarmament, but calls for the pursuit of negotiations in good faith relating to nuclear weapons.

With the end of the cold war, it was understandably hoped that the role of nuclear weapons in shaping the international system might become less relevant. Some people expected that nuclear weapons might be marginalised, or even abolished altogether; but unfortunately, they still have a major relevance 16 years after the end of the cold war. New nuclear weapons states have emerged, and new would-be nuclear powers have appeared on the world horizon.

The truth is that as far as we can see into the future, nuclear weapons will remain part—however much we hope they will be a diminishing part—of the global security setting. The knowledge to build them will continue to exist; they will not be disinvented. This country has set a good example in the reduction of its nuclear arsenal, but we should not think for a moment that if we were to divest ourselves altogether of that arsenal, other nations would be likely to follow suit for that reason, or countries known to be seeking a nuclear weapon would thereupon abandon their programmes.

As the right hon. Gentleman knows, my background was heavily affected by the cold war; my parents came from Estonia. In the past, I assumed that deterrence worked. Does the right hon. Gentleman have a view as to whether nuclear weapons truly did prevent a hot war arising between the west and the east, or, in retrospect, does he think that we overestimate the impact of our having had nuclear weapons? I am equivocal about that myself, and I wonder what the right hon. Gentleman thinks about it.

All we can go on is the evidence of history. The hot war—to use the hon. Gentleman's phrase—did not happen. One of the factors that brought the cold war to a peaceful end was the strength shown by the western alliance—by NATO—not only in having independent nuclear deterrents in Washington, London and Paris, but also in deploying, as an alliance, theatre nuclear weapons, which was highly controversial at the time, as we all remember. The hon. Gentleman should remember that point when he comes to vote this evening.

I was very struck by the speech in the House of Lords on 24 January of Lord O'Neill of Clackmannan, a former colleague in this House who was the Labour party's defence spokesman in the period when it championed unilateral nuclear disarmament. He said that when Lord Kinnock and other Front-Bench colleagues of the time

"started visiting the decision-making centres of the other nuclear powers—Washington, Paris and Moscow—and spoke to the Chinese in London, we were startled by the indifference with which they greeted our willingness to give up our nuclear arsenal. They felt that it would not be a bad thing, but would make not one whit of difference to their nuclear capability or willingness to participate in disarmament negotiations one way or the other."—[ Hansard, House of Lords, 24 January 2007; Vol. 688, c. 1120.]

He added that those experiences marked the beginning of new Labour in foreign and security policy.

For the policy we are currently discussing above all others, it remains the case today that laudable idealism must be leavened with gritty realism. In terms of numbers, there have been large reductions in the American and Russian arsenals, but within the last 10 years we have also seen the Indian and Pakistani nuclear weapons tests, the modernisation of China's nuclear arsenal, North Korea's proliferation, the discovery of Iran's covert nuclear programme and the evolution of Russia's nuclear doctrine, placing increased emphasis on nuclear weapons to offset its conventional weakness. All that demonstrates that the nature of the long-term threat to the peace of the world from nuclear weapons has changed but has not necessarily diminished. Indeed, according to "Strategic Trends", an independent view of the future produced by a body in the Ministry of Defence,

"access to technology that enables the production and distribution of chemical, biological, radiological and nuclear weapons is likely to increase."

That view certainly seems to be borne out by what we see around the world.

The right hon. Gentleman is giving a fine exposition of traditional Tory policy in the area under discussion, but does he agree that the key issue—which will be debated today, given that the selected amendment addresses it—is timing? Does he accept the Government's verdict on the timing? That is an important question, bearing in mind the fact that the Opposition accepted the Government's argument about weapons of mass destruction, which was found to be fallacious.

Of course, timing is a very important issue. I agree with the Government's view, and I shall say why shortly if I may proceed with my speech, but I feel that the subject under discussion and the decision to be made are sufficiently important that I need to set out why in principle the Opposition support the decision, as well as our views on the details of the timing.

"Strategic Trends", the document I was quoting from, states that

"the proliferation of nuclear weapons....particularly to weak and unstable states will increase the risks of more uninhibited, assertive and intemperate behaviour" by those countries. Furthermore, it states that

"states with nuclear weapons, such as Pakistan, possibly North Korea and potentially Iran will remain vulnerable to instability", with the possibility of the collapse of central authority and nuclear material falling into the hands of hostile regimes. In summary, it states that

"accelerating nuclear proliferation will create a more complex and dangerous strategic environment, with the likely clustering of nuclear armed states in regions that have significant potential for instability".

The decision on which the Government are seeking the endorsement of the House tonight would enable us to have an independent nuclear deterrent until at least the 2040s and possibly into the 2050s. We cannot, of course, see 50 years into the future, but that is the whole point. While none of the existing nuclear weapons powers poses an imminent military threat to the United Kingdom, to retain our deterrent is, in the words of the Defence Committee, to maintain "the prudent hedge" against an unknowable and possibly unpleasant future. It represents a vital ability to deter potential aggressors who will be both more diverse and less predictable than in the past.

The right hon. Gentleman did not mention Israel in his list of nuclear states. Does he accept that Israel's possession of nuclear weapons is a major destabilising factor in the middle east and that it is encouraging Iran to acquire nuclear capability; and what is his policy on dealing with that matter?

People cite the example of Israel having nuclear weapons, although I suspect that if we had been in Israel's situation over recent decades we would have wanted to have nuclear weapons, so I am not going to give advice to the Israeli Government about that.

The realistic planning that I have been speaking of has to assume that the UK will continue to be engaged in regional hot spots, including—but not limited to—the middle east, and that British military operations might have to be conducted in the face of local states possessing weapons of mass destruction of some kind. Nuclear capability, even when its use seems remote, significantly enhances confidence in dealing with a potential adversary.

As will of course be pointed out in this debate, we cannot know that any situation will arise in the coming decades where we will need the threat of our deterrent; equally, we cannot know that no such situation will arise—and, indeed, arise quite quickly. Let us think of our predecessors in this House of 100 years ago—of 1907. They were entitled to think that they were living in an age of fairly assured peace and constantly rising prosperity, with nothing more serious than regional wars in the previous half century. They had no inkling that within 40 years they would face the two greatest cataclysms in human history—calamities which could only have been reduced in scale had they been better prepared for them. With the sobering example of previous centuries before us, and with all the evidence in this century—from the middle east in particular—pointing to the next few decades being, if anything, more dangerous than the last few decades, I have to subscribe to the view that the abandonment of our nuclear deterrent would be extraordinarily ill advised, and, indeed, a national act of folly.

The right hon. Gentleman has talked about our predecessors of 100 years ago. Does he accept that his point would be even more powerfully made if our predecessors of 80 years or 70 years ago were mentioned? Understandably after the shocking experience of the first world war, they sought disarmament for the best of motives, but they could not have anticipated the rise of the dictatorships in Germany and elsewhere that plunged the world into an even worse disaster, and which might have been mitigated, or possibly avoided, had the western democracies maintained a strong defensive stance.

The right hon. Gentleman makes a powerful point that supplements mine. In the run-up to that great world crisis in the 1930s, we would have been better able to respond, and to try to avoid it, if this country had been in a position of military strength rather than weakness.

The right hon. Gentleman referred to events of 100 years ago. Of course, 100 years ago we had the British empire. Even when I was at school, the map of the world was coloured red. [Interruption.] Well, I am not as old as some in this Chamber. What we should be discussing is Britain's role in the world at the current time, with the nuclear issue being a part of that debate.

Of course this debate is about our role in the world at present, which is why I am talking about the middle east, North Korea, Iran and elsewhere. I am simply pointing out that, in deciding on what should be our current role in the world, we have to be conscious of the lessons of history; otherwise, we will repeat some of the mistakes of history, such as that to which Mr. Raynsford has just referred.

I appreciate that the right hon. Gentleman is a distinguished historian, but I am sure that 1907—not that I personally was around then—was the time of the great Anglo-German naval arms race. The Dreadnought was the weapon of mass destruction of its time. Does the right hon. Gentleman not accept that that arms race was a contributory factor in causing the awful war that broke out in August 1914?

First, that arms race had not started in 1907. Secondly, we are not talking about an arms race—this country is getting rid of 20 per cent. of its warheads, and it has got rid of 70 per cent. of its previous stock of warheads. We ought to bear it in mind that if the arms race before the first world war had gone in the same direction as current Government policy on the stock of nuclear warheads, there probably would not have been a first world war.

I have nothing but respect for those who wish—

Will the right hon. Gentleman give way?

Go on, then.

All Members of the House have enormous respect for the right hon. Gentleman and we do understand the arguments that he is putting forward. However, the logic of his position is that if every single state in the world were given a nuclear weapon, the world would be safer. That is nonsense, is it not?

That is not the logic, and it is the reason why we have the non-proliferation treaty, to which we are signatories. Everything that the Government have proposed is in line with that treaty, as is resisting other states developing nuclear weapons. By the way, I have the greatest of respect for the hon. Gentleman, as well; we North Yorkshire MPs have to stick together. However, he must not think that if we announced today our intention not to have a nuclear deterrent in future, other countries—those in Tehran, for example—would say, "What a relief! We are now going to abandon our nuclear intentions." That is not the way the world works, as he and I know; we simply have to make the realistic decision.

I have nothing but respect for those who wish the world could be free of nuclear weapons—most or all of us do—but our own total disarmament would no more make it so than wishing it so would. Crucially, the absence of our own nuclear weapons would make us more dependent, not less, on the United States of America. It is perhaps a paradox that those who oppose this decision are often among the fiercest critics of the United States; yet, in the ultimate crisis, such people would leave our security wholly dependent on the credibility and resolve of the White House—or of the Élysée—and its readiness to risk everything for the sake of Britain. Can we always be confident of that—that that would apply to the occupant of the White House for decades to come? I do not think that we can have that confidence.

For all these reasons, the arguments in principle for replacing our deterrent therefore seem to me overwhelming. The risks of not replacing it far outweigh the difficulty and expense of doing so. Furthermore, the advantages of a submarine-launched system, which is as invulnerable to attack as any weapons system in the modern world can be, also seem overwhelming. So we support the maintenance of a continuous at-sea deterrent, which until now has necessitated possession of four ballistic missile submarines. We would of course like to know when the Government think it will be possible to decide whether the new class of submarines can operate with only three vessels. The alternative of submarine-launched cruise missiles has also been suggested, but we share the Government's judgment that that would not only require the development of new technologies, but would require a submarine to be far closer to its potential target to have any deterrent effect. We also share the Government's view that the possession of ballistic missiles that can be launched from anywhere in the world toward anywhere in the world is an important part of successful deterrence.

Several hon. Members:

rose—

Let me make a bit of progress. I want to leave time for other Members.

I hope that the Secretary of State for Defence will say more when he winds up about cost—questions have already been asked about that—on which a fourth submarine would obviously have a major impact. One witness to the Defence Select Committee, Dr. Jeremy Stocker of the International Institute for Strategic Studies, has argued that

"the cost of the new submarines seems very high", suggesting that the current fleet of Vanguard-class submarines costs a little under £6 billion at current prices, if the cost of warheads and missiles is considered separately. The Government's estimate for the new submarines, however, has come in at £11 billion to £14 billion. If these figures are indeed correct, I hope that Ministers will explain in more detail why the costs are expected to be so much higher.

The Government have stated that the cost of UK participation in American plans to extend the life of the Trident D5 missile will be about £250 million. It is not clear whether there will be further costs, in order to extend the life of the missile, if necessary, into the 2040s. We would also be interested to know how much the detailed concept work shortly to commence on the Vanguard will cost. Can the Secretary of State provide an estimate of the cost of the work that will be undertaken in the period of the comprehensive spending review?

Much of this debate will of course turn on a further important issue that has already been raised by Members—whether the decision in principle to design and build a new class of submarines must be taken now. The Government have said that the process will take 17 years, and that because the first two Vanguard-class submarines will come to the end of their service life in 2022 and 2024—even with a five-year extension—the continuous at-sea deterrent cycle could not be maintained after 2024 if the first replacement was not ready by then. It is said that the different construction of the United States' Ohio-class submarines allows their service life to be extended well beyond that of our Vanguard class. I hope that the Secretary of State will go into more detail on comparable decisions to be made about the life cycle of the new submarines. Are the Government intending to build submarines with a life span of more than 25 to 30 years in future? What trade-offs in terms of capital costs and maintenance are involved? These issues need careful examination in future, but the timetable of the commitment that we are asked to make today is of course determined by the life span of the old submarines, and we have no reason to doubt that the early 2020s are likely to see the end of the service life of the first two.

Others have attempted to argue that past experience suggests that a period of 14 years is necessary to design and build new submarines, rather than the 17-year period claimed by the Government, for which they have given a reasonable justification. The truth must be that we cannot be sure how long it will take up to 17 years, but the eager seizing on 14 years seems suspiciously like grabbing at a date that is just the other side of the next general election. For a party split exactly down the middle on this issue, that is politically understandable, although it is not the way in which this vital national decision can be made by a potential party of government.

I thank the right hon. Gentleman for being generous with his time. Does he agree that if we do not go ahead at this stage, the design team that is in place to design the submarines will be dispersed, we will be unable to put a team back together and we will end up having to buy American submarines, thereby not taking advantage of this country's engineering capability?

The hon. Gentleman makes a very strong point, which I want to add to. However, I have not quite finished with our friends on the Liberal Democrat Benches.

The Liberal Democrat policy paper on this matter said that the period between now and 2014

"should be used to allow a clearer picture to develop concerning the proliferation of states that possess nuclear weapons and their ability to directly threaten Britain".

The trouble with that is that when we arrived at 2014, we would still not know—even if the world was, against all indications, becoming a more peaceable place—what threats we might face in the 2040s. However, if the world had taken a turn in a more dangerous direction, it would by then be too late to prevent us from having a significant gap for several years in our continuous at-sea deterrent in the mid-2020s. That is like building a house for the next half century and deciding on the basis of the weather in the next few months whether to bother with a roof. That is not a viable policy.

Of course, because the uncertainties in these time scales are so great, the only way to time such decisions is with a sensible precaution, providing a reasonable time buffer. We should have very—

Will the right hon. Gentleman give way?

Oh well, to be polite I had better give way to a Liberal Democrat.

The right hon. Gentleman mentioned the cold war earlier. Does he agree with former President Gorbachev, who said that

"A responsible course of action for the...Government would be to postpone the decision on the future of the nuclear arsenal at least until the next review conference of the NPT in 2010"?

For all the reasons that I have given, I do not agree with former President Gorbachev about that. Of course, Russia still possesses some 10,000 nuclear warheads. We are being told to get rid of our 160 warheads, which is the number that will be left. We of course need major contributions to the disarmament process from Russia, and we have seen some in recent years; however, I do not agree with President Gorbachev's judgment. This country will derive the strongest leverage and the strongest negotiating position from making the decision that we are now asked to make, not from shirking that decision.

As the right hon. Gentleman knows, the submarines are to be based in Scotland, which has the greatest opposition to the renewal of Trident. Some 80 per cent. opposed it in the last opinion poll. Why should the submarines be based in Scotland; and would he respect the views of the Scottish people as expressed through their Parliament, if it decided to vote against Trident?

These decisions are made on a UK basis, as the hon. Gentleman well knows. I do not think that the people who do such a tremendous job in Faslane and other locations in Scotland would thank him for saying that those facilities should be closed. The decisions are made on a UK basis, and that is the right way for them to be made.

We must have very serious regard for the point made by Mr. Hoyle about the maintenance of the relevant base of industry and skills, noting that the delay between the commencement of the Astute class submarine building programme and its predecessor evidently contributed to delays and higher costs in the Astute programme. The Government rightly intend, subject to satisfactory arrangements, that the new submarines will be built in the United Kingdom. The Defence Committee was advised by Mr. Murray Easton of BAE Systems that

"if there is a further delay, or any delay, in the submarine ordering programme it will have a significant and, I think, catastrophic impact on our ability to design and build and, therefore, for this country to have its own nuclear submarine design and construction".

That would of course include nuclear-powered conventional submarines as well as nuclear-armed submarines. It seems to us therefore that to wait several years would run not only a strategic risk but a very serious managerial and financial risk that could make the entire programme more difficult and expensive to execute.

Will the right hon. Gentleman give way?

Now that I have been speaking for nearly half an hour, I feel that I should try to conclude, so I will not give way again.

The Government are right to avoid a politically motivated delay that would make the programme more expensive, and right too to emphasise that a great deal of work has to be done to ensure that there is what the White Paper calls

"a much greater collaborative effort between the MoD and industry than has been the case in the recent past."

I hope that the Secretary of State for Defence can assure us not only that the costs involved are necessary, but that the MOD will have the skills necessary to deliver any future submarine programme to time and on budget. I also hope that Ministers will invite the National Audit Office to monitor the contract to protect the public purse. That point has already been made.

Those are the reassurances that we would like to receive from the Government about cost and about the management of the whole industrial process. But our support for taking the decision to begin this work and for taking it now is unequivocal. Taking this decision, which is entirely within our rights under the non-proliferation treaty, in no way diminishes our authority to argue for the strengthening of that treaty—a point made by my right hon. Friend Mr. Redwood—and to try to counter the proliferation of nuclear weapons across the world. This country has an excellent record in that respect, not only in the ways I have already mentioned, but in ratifying the comprehensive nuclear test ban treaty and in ceasing production of fissile material for nuclear weapons. We hope that the Government will couple this decision with leading an intensified international effort to improve the non-proliferation treaty. It was signed more than 40 years ago, but the 21st century has produced a combination of challenges that the makers of the treaty could not predict. Those challenges include shortcomings in our ability to detect states covertly developing nuclear programmes; the need to bring new nuclear weapons states, which did not sign the NPT, into a framework where they too contribute to the non-proliferation regime; and how to respond to the rise of an extensive global nuclear black market.

All those problems need work, including the need to secure world stockpiles of nuclear material against theft; to strengthen the proliferation security initiative; and to strengthen the International Atomic Energy Agency. That work should go alongside this decision today. The efforts to help non-nuclear weapons states, such as Iran, with peaceful nuclear technology must be credible, and so must the united international resolve to prevent them from acquiring nuclear weapons in defiance of the NPT.

All that work—to prevent black market proliferation and to uphold the non-proliferation treaty—is of huge importance to our national security. But it will also be of huge importance to our security for four or five decades to come, acting within the terms of the non-proliferation treaty, to ensure that the United Kingdom can continue to deploy a weapon of last resort. That is why the Government are right to come to the conclusion that they have and why, if we were in their place, we would do the same. On that basis, the Opposition will support their motion tonight.

Thank you, Mr. Deputy Speaker, for calling me in this debate and allowing me to make a personal statement and contribution. It is a pleasure to follow Mr. Hague. I welcome this opportunity to tell the House—before the media—why I have, after much reflection, concluded that I cannot vote with the Government today and have tendered my resignation.

I thank right hon. and hon. Members on both sides of the House who have shown me great courtesy during my time as Deputy Leader of the House and in more recent days. I hope that I have discharged my duties diligently. I want to be remembered not so much for being the Government's representative in this House, but more for being this House's representative in the Government.

I am especially grateful for the strong support and kind words of my right hon. Friend the Leader of the House and of his predecessor, my right hon. Friend Mr. Hoon. It has been a privilege to serve this House and to do so with such distinguished colleagues.

My thoughts at this moment are with a former Leader of the House, the late Robin Cook, one of our truly great parliamentarians, who encouraged me to follow him into politics, who came to Edinburgh, South to help to secure my re-election and whose example guides me today. Robin knew that in politics one has to take tough decisions—and few decisions come tougher than resigning from Government. I have taken such a decision, and in doing so, like Robin, I leave the Government with no bitterness.

I am overwhelmed by the messages of support I have received, but in truth, even if I had stood here as a latter-day Thomas Stockmann, I would remain true to my convictions. I have served my Government loyally for a decade, and the same Government have served Edinburgh, South well. From the children in the new school buildings in Gracemount and Liberton, and at Craigour Park and St. Peter's, to the patients in our new royal infirmary at Little France, we owe this Government a great debt. In my constituency, thousands of local citizens and thousands of people in low-paid jobs have been lifted out of poverty through the leadership of this Prime Minister and the funding provided by this Chancellor; I have been proud to vote through these, and so many other measures.

After reading the White Paper, "The future of the United Kingdom's nuclear deterrent", I have concluded that it has no future—that this country has to become a country for peace, not a country for war. We have led the world in campaigning to meet the Kyoto targets. We have led the fight to eradicate global poverty. Now we must lead the world in campaigning for the eradication of the nuclear threat—and we must lead by example. As the poet and essayist Emerson said:

"The real and lasting victories are those of peace, and not of war."

I have seen colleagues wrestle with their consciences and lose their beliefs. That is not a path that I have chosen to follow.

I have been asked by colleagues whether any inducements have been offered to me to change my mind. Honesty compels me to say that I have. Dr. Lewis presented me with a complimentary copy of his latest publication in favour of Trident. He even signed it, but alas it came too late, so the efforts of that warmest of cold warriors were wasted on me.

Serving my constituents in Edinburgh, South has always been my priority. It has been a privilege to have served not just the Government, but, I hope, the whole House and my country in various capacities, as Under Secretary with responsibility for competition policy and consumer affairs; for construction and coal miners' compensation; for small businesses; for enterprise and social enterprises; and, until this week, as Deputy Leader of the House of Commons. Public service is indeed an honourable estate.

It is to this Government's credit that we have the opportunity to debate this decision, as I said from the Dispatch Box last week. Past Governments took such decisions in complete secrecy, without even consulting the full Cabinet, more out of fear of domestic opposition than fear of giving away our secrets to foreign enemies. I praise the openness of the decision-making process now.

Let me put on record my tribute to our armed services. My father served with pride in the Royal Air Force—in fighter command 85 squadron, flying a De Havilland Mosquito night fighter—fighting the Luftwaffe in the second world war. In my time, I know from chairing a major Kosovo refugee appeal about the tremendous work of our brave forces, saving lives and protecting people in the Balkans; they are the finest fighters and the finest peacekeepers in the world.

I also have direct experience of the cold war nuclear legacy, as I had some ministerial responsibility for our multi-million pound contribution to dismantling Soviet nuclear submarines. It was as a Minister that I visited the naval yards in Arkhangelsk—Archangel—in 2004 and witnessed the terrible legacy of rotting hulks leaking their toxic nuclear waste into the sea. It is so sad that this generation is having to pay for the mistakes of a previous one.

There are those who oppose any spending on defence and our armed services, but I am not one of them. There are those who argue that the decision is premature, but I am not one of them, either. Tough decisions must never be put off. However, there are those who question the wisdom of the £15 billion investment in Trident, and I am most certainly one of them, for I cannot foresee any circumstances in which this country or its territories would be threatened by a nuclear weapons state and we would need to retaliate with a nuclear strike, or where the threat of a nuclear strike by the UK would shape such a state's actions.

The truth is that we have led the world in decommissioning land mines and now in nuclear weapons. The world is watching us now. Let us be leaders for peace. Whatever the good intentions of the White Paper to ring-fence the budget, I remain concerned that funding will be diverted by future Governments from more pressing defence equipment needs.

I have another fear about the position in 10 or more years' time—the accelerating impact of global warming. In 1996, I represented Friends of the Earth at the Berlin summit on sustainable development. I believe that current predictions of dramatic, if not catastrophic, climate change by 2050 will be telescoped into a shorter time frame. I fear that rising sea levels will threaten coastal towns long before that time, displacing large populations here in Britain. I believe that we will need every penny available to invest and cope with re-housing and other consequences. Let us incubate the new skills, develop the new technologies and find new ways to fight global warming and climate change. What greater goal can we set our young people?

I now leave the Government over this issue. I recognise that others hold equally sincere but opposite views, which I can respect. Perhaps I am a little self-indulgent in that. But others can still not seem to make up their minds, and of them I am less tolerant. To maintain the present Vanguard submarines and delay a replacement decision is not a credible stance, and I shall not vote for such options. I will, however, vote against the White Paper for the reasons that I have given. I go with a heavy heart, but a clear conscience.

It is an honour to follow Nigel Griffiths and I commend him for the courage of his actions and the clarity with which he explained them to the House today.

I should like to address three points: the principle of the nuclear deterrent; the strategic context and the danger of proliferation; and the timing of the decision that we are asked to take today.

Members with differing views will go through the Lobby to support the amendment in the name of Jon Trickett. There will be those who oppose the principle of the nuclear deterrent, some of whom have done so for many years, whereas others have come to that view more lately. Others support the principle of the nuclear deterrent, but abhor the manner and timing of the Government's conduct of the issue. I believe that both views will be represented among Labour Members going into the Lobby, and both those views are certainly represented among my Liberal Democrat colleagues.

I readily acknowledge that we have had a vigorous debate, conducted in a tone of great respect, in the ranks of my own party; people who have held very strong views for many years continue to hold them. It is not my view, however, that now is the right moment for Britain to give up its nuclear deterrent. In many respects, we face a more dangerous situation now than we have for several decades. In the Vanguard system, we have a nuclear deterrent that, contrary to everything that has been said, is quite new. The youngest of the four submarines was put into service only six years ago, so by common reckoning, the system has about 20 or so years of life ahead of it. The capital costs of the system have been paid for. The moment when dangers loom on the horizon that we have not had to contend with over the past 10 or 20 years is not the right moment for Britain to renounce its nuclear weapons. I wish to put that on the record from the outset.

The Government ask for various practical measures to be taken, but they also ask for a great decision to be taken in principle. The practical measures on which the Government wish to embark are the concept and design work that will keep open the option of having replacements for the Vanguard submarine. The White Paper also refers to participation in the life extension programme for the Trident D5 missiles. If we had before us a simple appropriations motion, seeking the House's approval to proceed with those practical steps, I would have no difficulty whatever in supporting it—but that is not what the Government are asking.

Harold Wilson said that a decision delayed is a decision made. Both amendments are a fudge because they will allow the decision to be taken at a later date; in fact, they are predicated on a decision being taken at a later date. I therefore urge the hon. Gentleman to say exactly what he thinks should happen to the amendments.

Mr. Speaker has selected one of the amendments, but the two amendments in the names of Mr. Denham, Dr. Whitehead and Mr. Field are sound reasoned amendments. They make the pertinent point that the appropriate moment for the House to take the decision in principle should be at the main gate decision, which we know from the Government's own White Paper will be taken between 2012 and 2014. The Select Committee also arrived at the view that no final decision needed to be taken until the same time. I say again that if we were simply being asked to take the practical measures to keep the options open until that date, I would have no difficulty supporting it, but that is not what we are being asked to do. We are being asked to make the big decision in principle now.

There has been some wriggling and some discomfort—a question was asked at Prime Minister's Question Time today—but right hon. and hon. Members should be under absolutely no illusions. The motion on the Order Paper asks the House to support the decisions in the White Paper. Let me quote what the Prime Minister says in it:

"We have therefore decided to maintain our deterrent system beyond the life of the Vanguards... we have to decide now whether we want to replace them."

It goes on:

"We have therefore decided to maintain our deterrent " by building a new class of submarines. These are decisions that the House is asked to endorse. It is not a simple appropriations motion, subsequent to which the House will have the opportunity—when the contracts are let and the serious money is spent—for further scrutiny. No, this is a decision in principle.

I understand the difficulty that the hon. Gentleman and his colleagues face today. On the assumption that the Government motion is passed, will he give an undertaking that the Liberal Democrats will have a clear position by the next general election? When people vote in it, they need to know whether they will get a pro-Trident or an anti-Trident policy—or will the Liberal Democrats sit on the fence again?

The hon. Gentleman is wrong in thinking that we are in some difficulty today; we are in no difficulty whatsoever. It is perfectly clear to any rational person that this decision does not need to be taken today and we do not therefore feel any discomfort.

One of the things that the Prime Minister said when he produced his statement in December was that there was to be a great debate between then and the House coming to the decision that it is making today. I understand that the Labour party cancelled its spring conference, but I can tell the hon. Gentleman that our party had such a debate. We have arrived at a clear position, and if he is interested in it I will be happy to share it with him. The fact of the matter is that we have taken the view that I have already laid out before the House today. We support the deterrent and we will continue to do so. I said that the next thing that I wanted to do was examine the strategic context.

The hon. Gentleman talks about the Liberal Democrats having a clear position, so he presumably does not agree with one of his colleagues who, as I understand it, described the Liberal Democrats' position as a mishmash and as a compromise to get it through their conference. The hon. Gentleman tells us that if it had been a simple debate on acquisition today, he would have had no problem voting for it, but can he speak so confidently for all those sitting on the Liberal Democrat Benches?

Yes. The resolution of the Liberal Democrats was that these initial steps should be taken. However, I put it to the hon. Lady, who has sent a letter to Liberal Democrats in the past 24 hours, that she would be very well advised to look at the plank in her own party's eye before she starts to think that she can detect a speck in the eye of the Liberal Democrats.

rose—

I will not give way because I am going to move to the second phase of my speech, and I said that I would refer to the strategic environment.

The strategic environment now is potentially more dangerous than it has been for a good many years. We see that Iran and North Korea are taking serious steps to becoming nuclear powers and we know that that will trigger a reaction among their neighbours. In the middle east, Iran's neighbours are likely to feel that they must follow suit. It is very frightening that a variety of states in that part of the world might become nuclear powers. Similar regional proliferation could reasonably be anticipated if North Korea were to renege on the agreements it has recently made and went ahead with its ambitions to develop a nuclear weapon.

The strategic context is very dangerous, and that makes the forthcoming review conference of the NPT in 2010 all the more important. It should be Britain's objective to play as constructive, positive and progressive a part as it can at that conference, and we have done that in the past.

The hon. Gentleman began his speech by saying, and he is reiterating now, that this is not the time to give up Britain's independent nuclear deterrent. Will he clarify for the House in what sort of international security environment his party believes it would be possible to give up the nuclear deterrent?

I hope very much that the efforts that are being made towards multilateral disarmament, to which the Foreign Secretary restated the Government's commitment and to which Mr. Hague restated the Conservative party's commitment, involve sincere commitments. All sane and rational people should be committed to trying to rid the world of nuclear weapons altogether. If the processes running up to 2010 and those that might reasonably follow from it could stave off the dangers of the specific regional proliferations to which I have referred, and if the Americans and the Russians could get new energy behind the steps that they have already taken to reducing the number of their warheads, we might begin to develop a situation in which it is reasonable for Britain to consider giving up its nuclear weapons. However, there are an enormous number of "ifs" in that and if a week is a long time in politics, seven years is an eternity.

Several hon. Members:

rose—

I will not give way at the moment; I am laying out our position on this issue.

If a week is a long time in politics, seven years is a very long time and we are making this decision seven years before, according to the Government's own White Paper, a final decision will be taken and, on the estimation of the Defence Committee, seven years before a decision needs to be taken. We will do enormous damage to Britain's role and the part that we can play at the 2010 conference if, before that conference takes place, we declare that we will remain a nuclear power until 2055. We will forgo any opportunity whatever to play a leading part at that conference and be a force for good.

I note what the hon. Gentleman says, but is not the reality that to maintain the deterrent that we have now, we have to send a clear signal to those involved in the industry and in the execution of the work that we have a long-term commitment? If we do not give them that, we will not retain the skills and our capacity. Without that, we can have no future deterrent and we will remain vulnerable to those powers across the world that will continue to develop their nuclear capacity. Unfortunately, because we will not have the knowledge of what they are doing, we will fall even further behind. Is that not an invidious position in which to place this country?

We need to establish a policy for Britain and not for British Aerospace. With respect to the hon. Lady, I believe that British companies are guided by the basis of the contracts that they sign. If we sign a contract approving their doing the concept and design work, they will be rather more interested in that than in our sending some signal. In the process of sending the signal that she wants to be sent, we will send a signal right around the world that Britain was going to remain a nuclear power until 2055. The workers in British Aerospace will be rather more interested in the contract that the Government sign than they will be in getting the signal of the sort that she suggests.

I refer back to the point that my hon. Friend Willie Rennie made earlier. Former President Gorbachev was exactly on the mark when he said that Britain should not make a decision before the 2010 NPT conference. He added:

"The UK Government's rush to deploy nuclear missiles whose service life would extend until 2050 is...astonishing".

He is entirely right. I also refer to the comments of Kofi Annan speaking in November. He recognised the more dangerous strategic context to which I have referred and said:

"We are sleepwalking towards disaster...worse than that—we are asleep at the controls of a fast-moving aircraft. Unless we wake up and take control, the outcome is all too predictable."

He went on that to say that if Britain took the decision to renew our system now to take us through to 2055, it would inhibit and damage the part that we could play. [ Interruption. ] Yes it is what he said; it is pretty much exactly what he said.

The hon. Gentleman talked about receiving signals, but did he receive the signals given to the Defence Select Committee by the Royal Navy? It clearly understands the strategic importance of keeping our industrial base in this unique field and choreographing the important work that has to be done on our attack submarines as well as on our nuclear submarines. Does he understand that the delay that his party is calling for would deeply damage our skills base and its ability to continue this important work?

The hon. Gentleman misunderstands me. I have not called for any delay in the programme of building. I acknowledge the Government's timetable, I have talked to British Aerospace and I have been to Barrow and discussed the implications. I have not called for the build to take place at a different time from what the Government say; I am talking about the point at which Parliament should approve it. In my view, the approval of Parliament should be given at the final main-gate decision when the big money is going to be spent and when the contracts are going to be let. I am not saying that the bill would be any later than the hon. Gentleman would wish it to be.

It is a cop-out.

rose—

The hon. Gentleman says that it is a cop-out and the Defence Secretary rises to his feet. If it is a cop-out, how come that is exactly the way in which the Thatcher Government did it with Trident? When they came to the House and said that they were going to embark on the Trident programme, the concept and design work had already been done, as the White Paper acknowledges. I am calling for the same procedure to be adopted at that stage next time as it has been this year. We have already heard from Members that much of the concept and design work for Trident was carried out in secrecy because the Government did not even want certain members of the Cabinet to hear about it. I applaud the Government for the openness of this procedure. It is good that there has been a White Paper and that there is a parliamentary debate. But they are not asking us to approve the concept and design; they are asking us now, seven years before they are going to let the contracts, to take a decision on the whole thing. It may be the last opportunity that we get for the best part of 50 years.

This is the first time that I have heard a Liberal Democrat spokesman say in a debate that a decision does need to be taken now. I have always understood the Liberal Democrats' position to be that this was not the right time to the make the decision. Will the hon. Gentleman make it clear to the House that if the position that he is now arguing is not that we should go back to the way in which things were previously done, it is quite avowedly that we should make a decision about the design and concept of a new fleet of submarines, but that we should not do that in any way that is informed by principle—because the principle does not need to be addressed now? That is what he is saying.

What I am saying is that the final approval of Parliament should be given at the point at which the contract is going to be let, when the money is going to be spent and when we reach the point of no return, as was said by the Defence Committee in its report and is said, in effect, in the White Paper from the Government. There is nothing particularly radical about that view. It is what the amendments tabled by the hon. Member for Southampton, Test and the right hon. Member for Birkenhead say. It is the meaning of the amendment that has been selected, which was tabled by the hon. Member for Hemsworth. It seems a perfectly rational view. It is one that many external commentators have picked up on. The Financial Times leader this morning commends exactly that course of action.

Let me make it perfectly clear to the Secretary of State for Defence that I am not objecting to the initial contracts for concept and design work, or the missile extension programme. They are perfectly responsible and if that was what we were being asked to debate today, there would not be any need to divide or go into different Lobbies, but that is not the issue. The Government are asking Parliament to write a blank cheque now and to forgo any further say on the matter for seven years and let the Government go on. We have not even had the detailed costings for the designs. It is a ridiculous stage at which to ask Parliament to make its final decision.

On that point, will the hon. Gentleman give way?

No, I will not give way to the hon. Gentleman. I have not finished making the point that the non-proliferation treaty requires us to act with all sincerity to try to bring about disarmament. I would have liked to hear a lot more from the Government, and to see more in the White Paper, about how they intend to take that agenda forward. I acknowledge the steps that have been taken. The right hon. Member for Richmond, Yorks was right to document them in his speech. They are all good progress. But the next significant round of multilateral disarmament negotiations will be the 2010 NPT review conference. I agree with the Select Committee, whose recent report deplored the lack of a convincing narrative from the Government on their strategy for that conference. We have not heard that narrative from the Government. If the Government on the one hand suggest that we should take a decision now that would make us a nuclear power until 2055, they should on the other give a far more convincing account of how they intend to push forward the course of multilateral disarmament, in the light of that decision.

Will the hon. Gentleman confirm that he has read appendix A of the White Paper, the two information sheets on non-proliferation issues that accompanied it, and the reply to the House of Commons Select Committee, which lists succinctly the non-proliferation efforts—both done and to come.

I have certainly read those documents, but, as I have just outlined, I remain unconvinced and I believe that the Select Committee remained unconvinced. It would not have issued a report in the terms that it did if it did not remain unconvinced. As I have already explained, the need for the final decision to be taken now has simply not been mapped out or explained by the Government in a way that I, or the Churches, or the Campaign for Nuclear Disarmament, or all the organisations that are lobbying us, find remotely convincing. [ Interruption. ] I say to the Secretary of State for Defence that there are a variety of external commentators who are looking at this matter and even those that clearly have a view on the principle of the issue, such as CND, are making the same point about timing as the Churches, the Financial Times and others. That point was also made in the amendment tabled by the hon. Member for Southampton, Test and the right hon. Member for Southampton, Itchen.

It is absolutely right that the ultimate political decision should be taken at the latest possible time. The Royal United Services Institute last week also made the point that a variety of decisions will be made over the next decade. It said:

"During that period further decisions will be required before the bulk of procurement money is actually committed, at which stage the decision will be binding."

That is the point. The big money decision will be at the point when the design work and the concept work has been concluded and the contracts are going to be let.

There is a reason the Government are so keen to have the matter decided now and it is entirely political. They suggest that we are the ones who have the political difficulty. I do not think so. This is straightforwardly an arrangement between the Prime Minister and the Chancellor to deal with the issue and put it to bed before the handover of power. The Prime Minister has a vision of himself as having saved the Labour party from unilateralism through the creation of the new Labour project, and his determination in bouncing the House into the decision now is to try to ensure that, as part of his legacy, that decision has been made and the Labour party in the country is bound up in his vision of Britain for another generation to come. In effect, his objective is to continue to rule the Labour party from beyond the political grave. The decision is not necessary at this time and it is an outrage that the House is being asked to make it at this time. We should take the decision in 2014, when the contracts are let, and I will vote accordingly this evening.

I beg to move, To leave out from "House" to the end of the Question, and to add instead thereof:

"notes the Government's decision, as set out in the White Paper The Future of the United Kingdom's Nuclear Deterrent (Cm 6994), to take the steps necessary to maintain the UK minimum strategic nuclear deterrent beyond the life of the existing system and to take further steps towards meeting the United Kingdom's disarmament responsibilities under Article VI of the Non-Proliferation Treaty, but believes that the case is not yet proven and remains unconvinced of the need for an early decision."

In the few minutes that I have I want to tackle a number of arguments. I begin by paying tribute to my hon. Friend Nigel Griffiths for the friendship that he showed to Back Benchers in his recent post and more particularly for the friendship that he showed to miners waiting for compensation in my constituency and throughout the country. He was a good friend to the miners and did a huge amount of work during those years. He is now tempting the House into, in effect, an immediate unilateralist position. I want to argue that there is no reason for us to proceed immediately in that direction.

First, I want to remind Members of exactly what these weapons are, because that seems to have been forgotten. They are the most destructive instruments that mankind has ever been able to create. The Nagasaki bomb killed 140,000 human beings. The weapons that we have now have eight times that capacity. There is the capacity to kill—to fry, in effect—1 million people with the explosion of a single device. Our submarines have the capacity to deliver 48 of those. We are talking about a huge destructive capacity—an awesome capacity—which we must all think very carefully about. It is that thought that leads me to the position that I have adopted and to the argument that I want to try to develop in the few minutes that I have at my disposal.

It seems to me that the Secretary of State made little of what is, in a way, the most important point, which is that the debate is taking place this afternoon thanks to the Government's finding the time. I pay due respect to the Government and to the Secretary of State for the good-spirited way in which the debate has been handled. But, frankly, the arguments that have been deployed are specious. I want to look at three of them.

The first argument is about unilateralism. A straw man has been erected in relation to the amendments in the names of 113 Members. It has been argued that, somehow or other, a unilateral decision has been suggested. The fact of the matter is that the only unilateralists in the House are those who are arguing for unilateral rearmament now. What I would like to see, as I am sure many hon. Members would, is a period of time during which we can get the arguments right and enter a process of multilateral discussions, possibly leading to a round of disarmament, under the NPT, which we are legally obliged to undertake—

Will my hon. Friend give way?

No.

We are legally obliged to undertake such discussions by a legally binding treaty. The talks are only two years away. Indeed, I understand that there will be a prep conference in May. It is extraordinary that we should unilaterally be deciding effectively to begin the process of rearmament within weeks of a legally binding obligation to begin multilateral negotiations on non-proliferation.

Will my hon. Friend give way?

No; I want to make some progress.

The amendment, which is in my name and that of many dozens of hon. Members, deliberately allows for a period of time before the next round of talks in which the arguments can be properly deployed and the debate can be properly argued. It seems to me that there would be the possibility at that stage of either unilateral disarmament, or the process of rearmament that the Government are proposing. The amendment would allow both approaches to be followed.

May I draw to the attention of my hon. Friend a quotation from Eisenhower? He was certainly no sandal-wearing hippy, and he said:

"In the councils of government, we must guard against the acquisition of unwarranted influence, whether sought or unsought, by the military-industrial complex. The potential for the disastrous rise of misplaced power exists and will persist. We must never let the weight of this combination endanger our liberties or democratic processes."

In the light of that quote, what role does my hon. Friend think that companies such as British Aerospace have had in our decision-making process?

My hon. Friend makes a telling point by referring to a Republican President. There is no doubt at all that British Aerospace has many excellent work people with all kinds of engineering skills. One should pay attention to that skills base. However, it seems that the Government lapse from time to time into the argument that the reason behind the decision is industrial, rather than political or in terms of defence.

I challenge my hon. Friend, or any other hon. Member, to find one quotation from a Minister that advances that argument. It has never been advanced in this debate—not once. My hon. Friend should not claim that it has been, because it has not.

I accept the point that my right hon. Friend makes in all honesty. However, even this afternoon, people speaking in support of the Government's case have made precisely that point.

I want to move on to address equally specious arguments that have been developed, such as that about the reduction of warheads. Obviously, the destruction of any warhead is a welcome development, so the Secretary of State's announcement in the White Paper—this was reaffirmed today—that the number of warheads would be reduced was good. However, that is not a non-proliferation measure. Everyone who has read the Defence Committee's report knows that the number of warheads active on the seas will still be 48. There will thus be no non-proliferation. While it is welcome that the stockpile of warheads in the UK is being reduced, that is not an argument that we are complying with our legal obligations to engage in non-proliferation. The Select Committee report clearly makes that case.

The Defence Committee was unconvinced about the timing. Paragraph 7 of the conclusions and recommendations of its ninth report says:

"Neither the White Paper nor the exchange of letters between the Prime Minister and the US President"—

I will refer to them later—

"explain adequately why decisions on UK participation in the...missile life extension are required by 2007."

If the Select Committee is unconvinced, so am I. Frankly, many aspects of the report argue clearly that it would be possible to delay the decision for some years.

Will my hon. Friend give way?

No.

rose—

I give way one last time.

Was the hon. Gentleman as impressed as I was by the detailed evidence provided by independent experts from both sides of the Atlantic that argued that the life of the current Vanguard class could be extended by 20 years, not the five years argued by the Government? That suggests that the timing of the decision is political, rather than strategic.

The point stands for itself.

I quickly want to move on to address the question of legality. Many legal opinions have suggested that the Government's proposals are not compatible with our article VI obligations under the NPT. I wrote to the Attorney-General to find out whether the Cabinet had received a legal opinion on the matter. The reply that I received today does not indicate whether the Cabinet did receive a legal opinion. However, the reply clearly says—in so far as the legal position is justified—that the Government are bound to act in good faith to bring about disarmament, but that there is no time scale in which to engage in that. If we are bound to do something and to act in good faith, yet the Attorney-General says that we can do so whenever we choose, that is not actually acting in good faith. If that is the best legal case that the Government have, it is a very weak one.

rose—

I am not going to take any more interventions, because I am running out of time fast.

For those reasons and a range of others, I do not think that we need to make a decision today. We should not take a decision, because the Government have not convinced us.

Finally, I want to refer to the exchange of letters between the Prime Minister and the President. Some 72 hours after the White Paper came out as a consultation document, the Prime Minister sent a letter, on 7 December, to the President in which he wrote:

"We have therefore...set in train the steps necessary to maintain our current submarine-based nuclear deterrent system".

I asked the Attorney-General's view about the letter because it seemed to be a binding commitment effectively to bring about the process of beginning to rearm. The rest of the two letters referred to the missile system.

The Attorney-General's response failed to convince me that a decision has not already been taken. This afternoon's debate has thus been pre-empted by a Government decision. That is a serious charge to make, but the letters stand in an appendix to a Select Committee report for any Member to have a look at. If that is the case, surely the Government ought to say clearly where we stand legally. Today's edition of The Guardian reports that work has already begun on the process of rearmament. I wonder whether the House's decision has been pre-empted. The Attorney-General's letter tells me that the Government will have regard to any vote of the House today. I hope that the House is the sovereign body in this country. If we were to choose to delay, or to refuse to accept, the decision, I would hope that we had not already entered into an agreement with George Bush that would effectively pre-empt the House.

If the amendment falls—as it might; I do not know—I recommend that hon. Members vote against the substantive motion.

Whatever the merits of the debate, the Royal Navy, Aldermaston and British companies have, with our American allies, maintained a continuous at-sea deterrent for many decades, which is an astonishing achievement of which they should be proud.

In this Parliament, the Defence Committee has conducted three inquiries on the future of the UK's strategic nuclear deterrent. We have intended—successfully, I think—to encourage and inform a comprehensive debate on the future of the deterrent. I pay particular tribute to the members of the Select Committee for the constructive way in which they have carried out these controversial inquiries.

The White Paper is an important document. This is the first time that we have had such openness and such a debate at this stage. I welcome that, and I think that the courage of the Government in coming to the House in such a way should be commended. I have been waiting for this debate to make my conclusions. I do not want to disparage those who take a different view—I have found the decision extremely difficult.

First, I would like to go through the arguments against the Government's proposal. This is an awful lot of money to spend on something of doubtful usefulness. At a time when we are funding our armed forces at a peacetime level, this seems an odd priority. We believe that we are the closest allies of the United State of America, and what do we add by buying this deterrent? We add a bit of uncertainty in the minds of the potential aggressor, but that is an awfully expensive bit of uncertainty. And how can we say to North Korea and Iran, "We can, but you can't"? It is not that our going for unilateral nuclear disarmament would have any persuasive power with them—clearly it would not—but making such statements does reduce our moral authority.

The Government have made little attempt to explain how deterrence works. The purpose of having nuclear weapons will have failed if we ever have to use them, yet the only point of having them is that someone might think that we might use them. It is on the basis of such arguments that we are spending £20 billion. When could we use them? Perhaps the only scenario is that the United Kingdom will not know who has exploded a nuclear weapon, and then what would we do? Could we use them in retaliation? I believe that retaliation, as such, is illegal. We can use them to hit back in self-defence, but by the time that we are involved in a nuclear exchange, all thoughts of stopping anyone else doing anything again will be long dead, along with most of us. Perhaps those rules are suspended in war, but that is far from clear. Legally, perhaps we could only use the weapons if we were firing them in first use, and that is a rather scary prospect.

The Foreign Secretary said that the deterrent was an "insurance policy" against an uncertain threat, but talk of an insurance policy is simply wrong. If someone destroys a house, the purpose of an insurance policy is to pay to rebuild the house; it is not to destroy the house of the person who destroyed it. Let us find a better analogy. The best one that I can think of is a booby trap. The Secretary of State assures us that if someone walks into our "house", there is a likelihood that that devastating booby trap, wandering round the oceans of the world, will go off. That is not like any insurance policy of which I have ever heard. In what circumstances could the horribly high rate of collateral damage caused by a nuclear weapon be justified? It is hard to deter those who have a religious conviction that death is better than life, or who are irrational, so the weapons are aimed at a tiny proportion of the threats against us—those from rationally led states. That is not a conclusive argument, but the equipment is very expensive for deterring that sort of threat.

I am not convinced that we can delay the decision; I think that we have to make it today.

The right hon. Gentleman has expertise as the Chair of the Select Committee on Defence. Could the UK purchase American submarines more cheaply, and delay the decision? I am asking him as an authority on such matters. Would that not be a possible strategy for the UK?

That is a good question, because the Secretary of State for Defence came before the Select Committee and said that there was no certainty that the Americans would sell us nuclear weapons. [Interruption.] Sorry, nuclear submarines.

As for the arguments in favour of the decision, given that other countries are pursuing nuclear weapons, it is an odd time to be disarming unilaterally. While our moral authority may be reduced if we tell Iran to do as we say, and not do as we do, our actual authority is increased by the possession of nuclear weapons. Unilaterally disarming would not have any beneficial effect on non-proliferation. Nobody reduced the number of their warheads when we reduced ours to 200. We gave ourselves moral authority by doing that, but countries such as Iran and North Korea were interested in military authority, not moral authority.

The world has become multipolar rather than bipolar, but it remains true that being strong discourages attack, and being weak can be an invitation to war. Theodore Roosevelt is quoted as saying:

"I have always been fond of the West African proverb: 'Speak softly and carry a big stick; you will go far.'"

I strongly believe that the UK does not want to be dependent on others, even including the United States, for deterrence. For those reasons, on balance, I am inclined to support the proposal, but I am deeply troubled by it.

Before my right hon. Friend leaves that point, will he consider one other factor? How could this country engage in a conventional response to conventional aggression if the people who initiated that conventional aggression had even one or two mass destruction weapons, and we had been unwise enough to give up all of ours?

I was a grateful recipient of my hon. Friend's brilliant essay on nuclear deterrence, which partly persuaded me. For the reasons that I have given, I have decided to support the proposal. I am not inclined to take the risk of allowing the unilateral nuclear disarmament of this country to send us naked into the conference chamber, as Nye Bevan once put it. The trouble is that those considerations apply just as strongly to Iran as they do to the United Kingdom. Why should we expect a proud Iranian nation to go naked into the conference chamber? It is a difficult question. My answer is that we have the world that we have.

We would like a world with no nuclear weapons in it, but there is not the smallest hope of achieving that without gradually reducing the nuclear weapons of those states that have them, while doing our utmost to ensure that no new countries acquire them. Will we succeed? I am sad to say that I doubt it, because I am profoundly pessimistic about the future of the world. Climate change has the capacity to make the planet uninhabitable for humans, and now that nuclear technology has been invented, it will never go away. There are nuclear weapons around, and sooner or later one or more of them will get into the hands of people who we would rather did not have them. We now have the ability to destroy the world, and I regret to say that it is natural human behaviour that when we have the ability to do something, sooner or later we try it out. I believe that that will happen before climate change has had time to do its work.

It is a great pleasure to follow my successor, Mr. Arbuthnot, as Chair of the Defence Committee. I share his concerns and, despite my previous views, I long ago reached the conclusion that nuclear weapons are a disagreeable necessity. Some say that we should retain strong conventional weapons, but I tell them that conventional weapons can be even more destructive than many nuclear weapons, so I cannot see the morality in bombing the hell out of cities with vast numbers of conventional bombs. There is no morality in that argument.

I am not an historian, but I am interested in history, and after the events of 1989 there was a naive belief that world peace was breaking out. That never happened. If we consider the past 400 or 500 years, we can see that major treaties that were meant to end warfare never did. Westphalia, Utrecht, Versailles and events after the second world war were followed not by the outbreak of peace, but by endless wars. One reaches the regrettable conclusion that if one takes the over-confident, liberal view—it is called that, but it does not have anything particular to do with the Liberal party, although I do not mean to be disparaging—[Hon. Members: "Go on!"] No, I will not be disparaging. Liberal Members are looking very uncomfortable, having conceded the need for nuclear weapons in principle. I do not mean to paraphrase George Bernard Shaw, but they have conceded the principle; now we are arguing not about the cost, but about the timing. The fact that they have conceded that principle is, in my view, a welcome step forward.

We are living in a highly dangerous world. To throw one's conscience at countries that do not share those liberal values is highly dangerous. I hate to be called a realist—although I have been called worse—but we have to accept the world as it is, not as we would wish it to be. A single submarine sailing the channels and oceans will not be the deciding factor in a nuclear conflict—it is just one submarine on patrol—but whatever phraseology one uses, whether or not we like the concept of insurance, it is a price worth paying. As almost everyone who makes the deterrence argument has said, it is a bluff; we never want to use the weapon, but it can deter others from using their weapons against us.

The question has been asked, how do we deter terrorists? It is not easy, but we should read French strategic thinking, because the French have thought deeply about the issue. They promise retribution to any state that arms terrorist organisations—not a full nuclear strike, but a response nasty enough to deter.

Will my right hon. Friend give way?

No, I am sorry I cannot. There is a time limit.

We have to retain Trident and replace it with Trident. Some might think that exchanging one model for another is hardly a momentous decision, but it is. Furthermore, it is a decision that many people approach with pre-conceived ideas. This is not mea culpa, but I believed for some time that replacing Polaris with Trident was the wrong decision. I have never traded in my CND badge—as the Foreign Secretary did—because I never actually wore one or wanted to do so. My views were not unilateralist, they were pragmatic. I believed that taking a large chunk of the defence budget away from conventional forces was not a price worth paying. Subsequently, I have publicly recanted on several occasions the arguments I advanced at that time. My research assistant and I wrote the minority report to the 1980-81 Defence Committee report. We wrote a very good report, but on reflection it was tosh. Those who make similar arguments have not yet made that concession. Anybody opposed is making specious arguments. The arguments are not finely balanced.

Will the right hon. Gentleman give way?

No; I am sorry.

The right hon. Gentleman will get two extra minutes.

Even if I had an extra two hours, I would not concede. The hon. Gentleman can sit down and whinge as much as he likes— [ Interruption. ] I would bet on that.

The arguments are not between people with principle and conscience and those who lack those qualities. The defence of the realm is not just a pragmatic and moral issue; it has to be determined on the basis of conscience. It is difficult to argue to some people the case for spending the 3 per cent. of our defence budget that the Foreign Secretary set out, which is far less than I believe it would have cost to replace Polaris by Trident. Then, we were talking about 15 or 20 per cent. of the defence budget, which was wholly erroneous.

In those days, when I had changed my mind about the replacement of Polaris by Trident, I none the less always supported the Labour Opposition line because of what was in our manifesto. In the last three elections I voted for myself—a wise decision—on a manifesto that said that Trident would be an essential element in Government policy. I am standing by that, but people who lectured me 20 years when I was thinking of abandoning a manifesto commitment are now abandoning a commitment that was freely agreed to by the Labour party.

Will the right hon. Gentleman give way?

Provided that the right hon. Gentleman is brief.

Of course I shall be brief. The right hon. Gentleman was speaking so frankly that I wanted to give him an extra minute. He mentioned the proportion of the budget to be taken by Trident and its replacement. Does he agree that if there is to be a continual reduction in the overall defence budget, more and more will be taken from the conventional forces that he and I want to be robustly maintained?

This is not the place to argue the case for a significant increase in defence expenditure, but I have always argued for it—even against the right hon. Gentleman's Government. Every report produced by the Defence Committee between 1979 and 1997 argued that the defence budget should not slip further and further down. As to the specious arguments, I have heard nonsense about costs. They are the same sort of arguments that I delivered 25 years ago. Some say the cost will be £78 billion, yet the Secretary of State for Defence says it will be £15 billion over 15 years, and I believe him, so those claims are scare tactics.

What about breach of the non-proliferation treaty? For every academic who says that there is a breach, we can find people equally, if not more, reputable who argue that there is no problem with the NPT.

rose—

No, I am not giving way. The hon. Gentleman can make his own speech.

What about the argument on opportunity costs? That relates to the point made by Mr. Mates. There may be opportunity costs in spending £15 billion, but that could easily be remedied if the Government had the bottle to say that they regard almost 2 per cent. of gross domestic product in an increasingly dangerous world as inadequate.

Should we stay nuclear? I argue that we should. Should there be three or four Trident submarines? That is a matter of judgment, because if there is an accident three will become two, which will not give us a continuous presence. There are so many other arguments—

Order. The right hon. Gentleman's time is up.

It is a real pleasure to follow Mr. George, who succeeded me in the Chair of the Defence Committee, so we have now heard a triumvirate with broadly similar views.

Unlike some other speakers, I do not want to deal with the strategic issues that underlie the question of whether to maintain our independent deterrent. The House will not be surprised to hear that I agree that we should keep it, although the arguments in favour are quite different from the time when we were debating whether to replace Polaris with Trident, as my right hon. Friend Mr. Arbuthnot said, and the case is not as clear cut as it was then. I want to explain why I believe that if we update our deterrent, the sort of deterrent we need will be different from when we took that decision.

In 1980 the world was bitterly divided between blocs—NATO and the Warsaw pact—and in those circumstances it was no wonder that we maintained a 24-hour, 365-day a year deterrent. It consisted not just of the Polaris missiles, but of free-fall nuclear bombs, nuclear depth charges and Lance surface-to-surface missiles based in Germany. It was a formidable arsenal, but with the end of the cold war most of it has been stood down. No one today would seek to justify the level of deterrent we believed we needed then. The political and strategic picture is wholly different.

The different threat level is already reflected in the way in which the deterrent now operates—there is one submarine on patrol and I understand that it is at several days' notice to fire, rather than on continuous alert. Since 1994, the missiles have been de-targeted.

The level and immediacy of the threat is now regarded as so low that the submarines can undertake hydrographic work and join in naval exercises with other vessels. The sub-strategic deterrent that was considered essential now consists of one Trident missile with one warhead rather than a multiple weapons system. We should welcome that reduction in the size and scale of our deterrent posture; it fits with the times we live in and is consistent with our international obligations on the reduction of nuclear capability. A renewed deterrent will need to be equally flexible to respond to any changes in the strategic picture over its long lifespan. It will also need, in financial terms, not to be too much of a drain on an already over-stretched defence budget.

In considering a replacement for the current deterrent, the White Paper examines various options. It rejects the notion that a land-based system would be practical. Equally understandably, it rejects as too costly and impractical the notion of a surface ship carrying ballistic missiles. Finally, the option of an air-based deterrent with converted aircraft has been turned down, not least because cruise missiles are vulnerable to being shot down and are unreliable, and no nuclear cruise missile could be introduced without testing it—and such a test is forbidden by the test ban treaty.

The Government have rightly decided that the new deterrent will be based on submarines similar to the Polaris and Trident systems. The issue in 1980 was whether we needed four or five such boats in order to maintain a continuous deterrent. Today, the question is whether we could manage with three. I believe that the Government need to give serious consideration to both the number of new submarines and to their size. In their White Paper, the Government say the decision has yet to be taken on how many submarines will be required. Quite rightly, Ministers take the view that we must have sufficient submarines in order that a continuous at-sea deterrent can be maintained. I agree with that, but we need to consider whether and how we might devise a way of meeting that requirement in a manner that could reduce both the capital and the running costs.

Given the change in the strategic picture and the unlikelihood of a sudden massive attack that required the availability of an instant response to deter it, I believe that we should look at the possibilities of international co-operation to meet our deterrent needs. In that regard, we should explore the possibility of coming to an understanding with the French. Before eyebrows reach the ceiling, let me say that I am not talking about the security implications, simply about patrolling. The French see themselves as having a similar deterrent requirement to ourselves and they are in the process of updating their independent deterrent, but now with four submarines instead of five.

It has always been the position of successive Governments that the only way to guarantee one ballistic missile submarine at sea all the time is from a fleet of four. That relates to the right hon. Member for Walsall, South's point about the possibility of an accident. However, if an understanding could be reached whereby the at-sea and, therefore, invulnerable deterrent was shared between ourselves and France at times, it seems to me possible, or even likely, that each of us could manage with one submarine fewer. Such an arrangement need not in any way affect the integrity or independence of our deterrent, nor need there be any degradation of the security relating to targeting, pay loads, patrol patterns or anything else. It would simply involve an agreement over the timing of the departure and return of each country's deterrent patrol. There would thus be a guarantee of a European deterrent at sea in the unlikely event of a surprise or short-notice nuclear attack. Such a scenario may seem unlikely or even impossible as we speak, but we are talking about the uncertainties, both strategic and political, of the next 30 or 40 years. Had we been taking such decisions in 1980, when the right hon. Member for Walsall, South and I were debating this, and painting a picture of 30 or 40 years' time, we would have been seriously wrong about the timing of the ending of the cold war.

I immediately hear objections that one cannot rely on the French and that their priorities might be different from ours, but I do not believe that those form an insuperable barrier to co-operation. While a French deterrent patrol was at sea, we could maintain a submarine alongside, ready to sail in a matter of hours. I believe that a ballistic missile could even be fired alongside should an attack appear with no or little warning, unlikely as that is. I think that that is technically possible. However, that is not the threat we are aiming to meet because a no-notice attack is in the realm of the most unlikely, bordering on impossible, at the moment.

Last year, on a visit to Brest—the headquarters of France's deterrent forces command—I discussed this thought with Admiral Boiffin, the commander of all France's strategic deterrent assets. He readily agreed that there could be considerable cost savings on both sides if there were to be co-operation and he acknowledged that he could see no military objections, given the extreme pressure on defence budgets. But, of course, he added that it was not a decision for him but for his political masters in Paris. That is why I am putting it to our political masters in London. I commend this thought—it is only a thought—to the House as a serious way to try to maintain our deterrent in the most cost-effective manner.

The second area where I believe the change in the type of threat merits a change in the operation of the deterrent is over the size of any submarines. We can reduce their size and we do not need as many tubes. If we can get some sort of synergy between the next generation of ballistic submarines and the next generation of hunter-killer submarines, there are huge potential cost savings.

Overall, in replacing this deterrent we need to look for cost-effectiveness and co-operation, and a way to do that with the least impact on a defence budget that is already very stretched.

The House should not forget that the scale of indiscriminate destruction that can be unleashed by a single nuclear warhead is unparalleled. It was Nikita Khrushchev who said that in a nuclear war, the survivors would envy the dead. Almost by definition, nuclear weapons inflict death and suffering on civilians, and the suffering is not confined to those present at the blast. Descendants of survivors of Hiroshima and Nagasaki are still being born with genetic defects today. The House will be aware that the current generation of so-called small nuclear weapons are many times more powerful than the two dropped in Japan at the end of the second world war.

I spent most of my political life during the cold war. There was a very real fear in Europe in particular that there really would be a nuclear war. There was a recognition on the part of many of the leading countries, including the United States and Britain, that if nothing were done, it would only be a matter of time before a large number of countries acquired nuclear weapons. This was a terrifying prospect. Clearly the more countries that have nuclear weapons, the greater the chance that they will be used. It is against this background that the international community, with Britain playing a major role, resolved that the world should instead become free of nuclear weapons. In 1968, the nuclear non-proliferation treaty was agreed, and it was ratified in 1970.

At the heart of the treaty is a deal between the non-nuclear weapons states and the nuclear weapons states. The non-nuclear weapons states agreed not to seek to acquire nuclear weapons; in return, those states get assistance with civil uses of nuclear energy and, crucially, the promise of complete nuclear disarmament from the nuclear weapons states. It is generally believed that the non-proliferation regime, with the non-proliferation treaty at its heart, has played an important role in curbing the spread of nuclear weapons beyond the nine or so states currently believed to hold them. The treaty is, as Ministers have put it, the cornerstone of the international non-proliferation and disarmament regime.

The end of the cold war brought a window of opportunity to make real progress in fully implementing the nuclear non-proliferation treaty. The tragedy is that this is not the way in which it is turning out. In recent years, there has been growing disillusionment among the non-nuclear weapons states. They fear that the nuclear weapons states are not prepared to fulfil their disarmament obligations. The world's non-proliferation mechanisms desperately need strengthening. That window of opportunity still exists.

No country is better placed than Britain to make a major contribution internationally in this field. After all, neither Britain nor western Europe is subject to any direct military threat and the Government have stated that no such threat is foreseen. This is the time when Britain should be taking the initiative to encourage nuclear disarmament and non-proliferation. It is profoundly depressing that the Government want to procure a new generation of Trident.

The decision to buy a new generation of Trident would damage non-proliferation efforts. After all, we have an obligation to move towards complete disarmament, and making provision to renew Trident clearly runs counter to that obligation. We seek to persuade non-nuclear weapons states not to pursue nuclear weapons programmes, and we seek to persuade the international community of the need to strengthen the world's non-proliferation mechanisms. Those exhortations will be met with increasing cynicism if, at the same time as we make them, we buy a new generation of Trident. It will not be just our credibility that is damaged—faith in the world's non-proliferation regimes will be further undermined. By renewing Trident we will effectively say to other countries that nuclear weapons are so vital that we are prepared to spend billions of pounds to make sure that we have them in the 2020s and beyond, even though the Government admit that we do not face a foreseeable direct military threat. Far from persuading other nations to remain non-nuclear, we will send a signal that nuclear weapons are vital.

The Government argue that we should renew Trident, not because of any foreseeable threat, but because we cannot accurately predict the nature of the world in 30 or 50 years' time. Surely, the same is true for any country in the world. Germany, Japan and Egypt, for example, do not know what threats will face them in the 2020s and beyond. There is nothing in the Government's justification for renewing Trident that does not apply to every country in the world. That clearly undermines our argument that non-nuclear weapon states should continue to forgo nuclear weapons. The Government rightly say that we do not know what the future holds, but we can be sure that a decision not to renew Trident would avoid the damage that would be done to non-proliferation efforts if we go ahead with renewal.

I would like the UK to decommission Trident. Other countries have given up nuclear weapons: South Africa abandoned its nuclear programme, as has Libya, and Ukraine got rid of its nuclear weapons too. We applauded those countries for the course that they took. None of the countries that abandoned their nuclear programmes are any less secure, and neither would we be. Indeed, Britain would be a safer place if we did not renew Trident because, first, we would avoid the detrimental impact of Trident renewal on the non-proliferation regimes and, secondly, we could spend our defence budget more effectively. Instead of spending £20 billion on renewing Trident and £1.5 billion every year running it, Britain could put more resources into defence equipment and operations more relevant to our security needs in the 21st century.

The prospect of nuclear proliferation is as dreadful today as it was in the 1960s, when the nuclear non-proliferation treaty was agreed. This is a critical period, and the decisions that we make today will have an important bearing on the deployment of nuclear weapons world wide. Consideration of whether to procure a new generation of nuclear weapons should take place in the context of the role that Britain should play in the world today. My vision of Britain is of a leader in global non-proliferation, keeping our commitments and strengthening the world's nuclear safeguards, which is why I will vote against the renewal of Trident.

As my right hon. Friends the shadow Ministers know, and as I have indicated over the past six months, I cannot support the Government in the Division lobby tonight. The effective decision to replace Trident is premature, it has not been fully considered, and it is not justified. The debate is not about being for or against nuclear weapons. I was strongly supportive of Trident and our other nuclear deterrents during the cold war. Trident will be with us for the next twenty years, and possibly longer, so that is not the issue.

This debate is about the deterrent which, in 17 years' time, we will bequeath to the next generation. None of us can predict what international relationships will be like so far ahead, yet we are being asked to make a full commitment to a highly expensive weapons system that, in the event, could prove ineffective as a deterrent and is questionable in its justification. We are committing not ourselves but the next generation, who may have very different views on deterrence and, indeed, on which defence priorities we should spend the massive sums involved.

There are three key questions. First, do we need a deterrent? My answer is yes. In an uncertain world, it is surely better to deter aggression than to respond to it after it has occurred. To be successful, however, a deterrent must be proportionate to the perceived threat; it must be clearly effective and credible; and therefore need never be used. Belief in the aggressor's mind that there is the will if necessary to use that deterrent is essential to its credibility, which is why it must be proportionate. Cold war deterrents worked because the balanced threat of mutually assured destruction and the nuclear doctrine between two rational enemies who understood the consequences assured its success. Any future deterrent must be powerful enough to create fear in the potential enemy; its nature must be such that the enemy believes we would really use it if attacked; hence it must proportionate to the threat that the enemy poses.

The next question, which is crucial, is: does the deterrent need to be nuclear? Nuclear warheads are weapons of mass destruction. When we faced the vast Soviet nuclear arsenal, they made sense, because the Soviet bloc was a known enemy that posed a quantifiable threat. The nuclear arsenal of the West was sufficient to deter that threat and, in my view, it was proportionate to it.

Since 1989 things have dramatically changed. The enemy today and in the future is unclear and its threat is unquantifiable. Proponents of replacing Trident argue that there might be a revival of the Russian confrontation. That is a pretty long shot. Even longer is the scenario of a new cold war-style ideologically-driven nuclear arms race where our nuclear deterrent would once again become relevant. The only ideological conflict that I can see is one where it would not be a deterrent anyway, because of the nature of that ideology. We are told that Trident is an insurance against such remote possibilities, but £20 billion is a pretty hefty premium against a pretty unlikely threat.

Today's and, I suspect, tomorrow's threats come more from international terrorism and so-called rogue states. Iran is sometimes cited as encompassing both. Let us, for the sake of argument, assume that she could pose a nuclear threat to the United Kingdom. Does the House really believe that a British Government, even in response to an attack, would in the 21st century be prepared to obliterate Tehran? I do not believe that and, more importantly, I do not believe the Iranians believe it, yet that is the stark key to successful deterrence, and if that belief does not exist, it is not a deterrent.

The truth is that the idea of automatic reactive mass obliteration, which was so fundamental to the concept of mutually assured destruction, does not wash any more, and people in the west would not accept it. Yet Trident's credibility rests on it. To me, Trident was a deterrent of the 20th century; it is not a deterrent of the 21st. We should be looking for something more proportionate and therefore more credible, and that might well not be nuclear. If we need time to do that, we should make that time.

If the deterrent is nuclear, should it be Trident? Trident was originally chosen because it was mobile and invisible, and therefore invulnerable to pre-emptive strike. We are told that that is still the case today. But will it still be invisible in 20 years? That is the crucial question. Do we believe that, by then, advances in technology will not have found a means of tracking submarines underwater from space or from the sea itself? If so, Trident will be redundant and the massive expenditure will have been wasted. Are we prepared to bet against that?

Are there alternatives? Having chosen Trident, the Government are determined not to weaken their position by conceding that there might be alternatives. I understand that. They have a case to make. However, after pressing them for many months, I was pleased that they finally acknowledged that alongside the options in the White Paper, there has been research into the electromagnetic launch of projectiles to achieve hypersonic velocities, and that study of kinetic energy missiles has been undertaken, albeit now discontinued. My hon. Friend Mark Pritchard referred to those. I have heard also from other sources of more substantial research work into these technologies which suggests their potential to be developed into variable, non-nuclear but powerful weapons systems that could become credible deterrents.

That is what we should be exploring, yet such options are not even discussed by the Government in this debate or in the White Paper. In fairness to the generation upon whom we are effectively seeking to dump an irreversible commitment to "son of Trident", we should at least show that we have examined the options before doing so. I believe and have argued previously that before the House takes a final decision, we need a senior independent examination of and report on all the options, not just those in the White Paper. The decision is far too important to railroad through the House.

Do we have to decide now? American experts, including Professor Richard Garwin and former Principal Deputy Assistant Secretary of Defense Philip Coyle, tell us that on United States' experience, our submarines could also have their life extended significantly beyond present calculations. Indeed, Philip Coyle says that the Vanguards included later improvements on the US design and

"my hunch would be that because of the improvements made by the UK, UK systems would have longer lifetimes than US systems".

Whatever the exact truth, there is undoubtedly flexibility on time. The Government should use it to allow a proper assessment of their case to be made. Their failure to do so smacks of a rushed decision that will affect not us, but the next generation. We owe the next generation better than that. We owe them an honest assessment and a fully and responsibly justified decision. The White Paper and the motion offer neither of those. I will therefore support the amendment in the Lobby tonight.

There is no doubt that nuclear weapons are the greatest menace to life on this planet. Climate change is an immense concern, but as was shown in Al Gore's Oscar-winning film, "An Inconvenient Truth", at last week's European Union conference, and by this week's Bill, with effort it can be contained and even reversed.

The effect of nuclear explosions, on the other hand, is permanent and irreversible. I have paid my respects at the peace memorial at Hiroshima, where descendents of the original victims still pay the price of one day's folly. I have seen the Japanese city of Kokura, the intended target of the second atom bomb. When cloud prevented the bomb from being dropped there, the United States bomber crew, thinking it a pity to waste it, dropped it on Nagasaki instead, causing hundreds of thousands of immediate casualties and indefinite trauma from fall-out.

The Chernobyl explosion made lamb meat uneatable in Cumbria. If the nuclear power station at Three Mile Island had gone up, the effect of the so-called China syndrome would have caused irremediable havoc, not only in the United States but throughout the world.

When Neil Kinnock placed me in charge of the defence review after Labour's election defeat in 1987, it became speedily clear to me that the menace to Britain and the world of nuclear weapons could not be solved simply by Britain getting rid of Trident. There were then four other proclaimed nuclear weapons powers, each of them a threat to the entire planet, together with Israel, which has never admitted to possessing nuclear weapons but is universally known to have them. The only hope of reducing and eventually ridding the world of this threat was not by self-congratulatory unilateral action but by international negotiation. That is why my policy document, "A power for good", said:

"It will...be the policy of the Labour government to use all effective means to reduce nuclear armaments and to move towards the objective of a nuclear-free world.

The Labour Party believes that fully verifiable international agreements, achieved by negotiation with and between nuclear-armed powers, are the best way of achieving those ends."

That is why, when the Labour party's national executive approved that document, Neil Kinnock declared, when he discussed this issue with world leaders, that

"they were totally uncomprehending that we should want to get rid of a nuclear missile system without getting the elimination of nuclear weapons on other sides, without getting anything for it in return."

My right hon. Friend will remember that when we on the national executive were persuaded by his policy document, we made a commitment to try to come out of nuclear possession together with all the other smaller nuclear powers. Does he think that that part of the policy was ever honoured or that any serious effort was put behind it?

What I do remember is that the right hon. Lady supported the document before the national executive, as did Robin Cook.

At that time, when we were considering these matters, the German Foreign Minister said to me:

"agreements are better than unilateral moves because they can be verified and cannot be reversed."

That, of course, was after the Labour party's disastrous defeat in the 1983 general election on a manifesto that I called

"the longest suicide note in history".

That, of course, was when my right hon. and noble Friend Lord Kinnock was still hoping to become Prime Minister rather than a twice-failed Leader of the Opposition. And that, of course, was before India, Pakistan and North Korea had become nuclear weapons powers.

That shift of policy removed an insuperable barrier to the Labour party's electoral credibility. Without it, many of my hon. Friends would not be in this House today, including some who may be contemplating voting against the Government this evening. Do those hon. Friends really believe that our shared objective of world nuclear disarmament can be achieved by unilateral disarmament by Britain? Do they really believe that if we gave up Trident, the eight other nuclear weapons powers would say, "Good old Britain! They have done the right thing. We must follow suit."? Pull the other one!

Will my right hon. Friend give way?

If my hon. Friend will allow me, I should like to continue.

The only way in which we can give a lead in world nuclear disarmament is to sit down with the others and to engage in hard bargaining. That, after all, is how we achieved success at the Brussels climate change talks last week. Britain did not achieve that success by being absent or by opposing European Union membership—as we did, let us not forget, in the longest suicide note, long before our active and co-operative United Kingdom membership of the European Union enabled my right hon. and noble Friend Lord Kinnock to become a European Commissioner.

The Climate Change Bill on its own, however admirable, cannot bring about world action to remedy climate change. That requires international co-operation. Voting tonight to give up Trident will not persuade Israel and North Korea to give up nuclear weapons. Their threat will remain until international action is taken to reduce and remove nuclear weapons.

In my speech to the Labour party conference commending our defence document, I said:

"A move by a Labour government to get rid of nuclear weapons without agreement internationally could be reversed by a non-Labour government."

Defeating the Government tonight—which is what must be the intention, in all honesty, of anyone who votes against them—could so reduce our party's credibility as to contribute to a Labour defeat at the next election. Do my hon. Friends really believe that there is the slightest hope of a Tory Government not renewing Trident, given the opportunity, or of a Tory Government taking active steps towards international nuclear disarmament?

A cartoon in The New Yorker once showed an army officer in a bunker saying to his assembled troops:

"Gentlemen, the time has arrived for us to make a futile gesture."

Futile gestures can be personally satisfying, but what do they get us? I will tell the House what they get us: 18 years in opposition. It is one thing to revisit the scene of the crime; it is quite another to revisit the scene of the suicide.

When a Minister resigns on an issue of principle, as Nigel Griffiths has, one must pay tribute to his integrity. My right hon. and learned Friend Mr. Ancram made a brave and important speech this afternoon, and he also deserves a tribute for his integrity. I hope, however, that they will both forgive me for saying that I believe that they are fundamentally mistaken. I believe passionately that deterrence has been seen to work in the past and that it continues to be very persuasive for the future.

During the cold war, which could at any time have led to a hot war, I had no doubt that the Soviet Union would have contemplated conventional aggression but was deterred from doing so by the realisation on both sides that any conventional attack could quickly escalate into something far more awesome. That mutual restraint was a crucial consideration, and it differentiates countries such as the United Kingdom from some of the rogue states that might be contemplating acquiring a nuclear weapon. It was asked what difference it would make to a country such as Iran if Britain did not give up its nuclear weapons, but I believe that there is a fundamental distinction.

I would also say to my right hon. and learned Friend the Member for Devizes that even bad Governments, evil states and aggressive regimes can be deterred. They are not all irrational. We now know that, during the Gulf war, the United States made it clear to Saddam Hussein that, if he used the chemical weapons that he had at that time, he would invite a similar response. There is every reason to believe that that carried considerable credibility.

I had the privilege of serving as Defence Secretary for three years, and for having responsibility for our Trident programme at the time. However, it was not me but the Prime Minister who would have had to take any decision on the use of that deterrent. When I was appointed Foreign Secretary, however, I found that I was one of two Ministers nominated by the then Prime Minister to act on his behalf in the event of either his death or incapacity at a time of grave crisis for this country. That is a pretty sobering responsibility with which suddenly to find oneself. I share with all Members, including those with whom I disagree, the realisation that nuclear weapons, unless dealt with in a sane and responsible fashion, can have awful consequences for the world in which we live.

Why do I come to a different conclusion? I do so for several reasons, which I have no hesitation in sharing with the House. Of course, the cold war is over and the threat that we faced at that time is unlikely to reappear, but it is not guaranteed that it cannot reappear. We are going to live in a world in which the United States and Russia will remain nuclear superpowers for the foreseeable future. The two powers of the future, India and China, are already nuclear powers. What are the implications for western Europe? Were Britain and, I presume, France to be persuaded by the arguments that we have heard from certain quarters, would western Europe be unable to defend itself from the kind of threat that, however unlikely, could arise? In the context of half a century, we cannot assume that the nuclear umbrella that the United States has provided will necessarily continue to be available.

The likely problem has never been that we would be attacked with nuclear weapons, but that a nuclear-armed aggressor could say to a country disarmed of nuclear weapons, "Unless you concede to our requirements, we will threaten to use our nuclear weapons against you, in the knowledge that you cannot retaliate." That is what deterrence is about; unless we have the capacity to deter, we are able to be blackmailed and have no alternative but to concede.

Where does the amendment mention abandoning Britain's independent deterrent? Why do Members such as the right hon. and learned Gentleman have to put arguments that, in my view, are entirely specious—those questions are not being asked tonight?

If the hon. Gentleman will forgive me, we are debating not just the amendment but the whole principle of the relevance of nuclear weapons at this time. As he mentions the amendment, let me say that whatever decision is taken tonight, it is absurd to suggest that the House and the country could not reconsider that decision if, unexpectedly, there was the prospect of major progress on multilateral nuclear disarmament. The contracts for the new submarines will not be decided until 2012 at the earliest. Whatever Ministers might say, if the world moves in a much more favourable direction, decisions can be reconsidered and taken in the way the hon. Gentleman might wish.

We live in a difficult and uncertain world. Russia is not turning into a modern, democratic society as we might have wished, and is rearming in a significant way. Russia under President Putin is no threat to the United Kingdom, but who can predict who might rule from the Kremlin and have available nuclear weapons with which to threaten the peace of the world in the next 50 years? Only a few years ago, a Mr. Zhirinovsky, who, interestingly enough, led a party called the Liberal Democrats, made considerable progress in moving towards power in Russia. Of course, he has been rebuffed, but none of us can be certain about what will happen in that country.

The worry about the new states seeking to acquire nuclear weapons, such as Iran and North Korea, is that they do not have the tradition of restraint—until recently, India and Pakistan did not even introduce a hotline to minimise the risks associated with nuclear weapons. To imagine that this country's security would somehow be safeguarded in a world in which new nuclear powers are coming forward and in which, were the advice accepted, western Europe was to be the one region that not only did not have the capacity to deal with such threats but had by its own choice ceased to have that capacity, would be very foolish.

My right hon. and learned Friend the Member for Devizes referred, quite reasonably, to terrorist organisations. Of course we cannot threaten to use nuclear weapons against a terrorist organisation; but terrorist organisations are already seeking, and will continue to seek, to acquire the capacity to develop dirty bombs and other weapons of mass destruction, and they will look to rogue states—to Governments—to provide them.

We know already that some Governments have been willing to provide terrorist organisations with the most vicious armaments. It is those Governments whom we can deter by making clear, as we must, that in the event of any attack involving weapons of mass destruction—certainly nuclear weapons—we would not simply go for the terrorists concerned. We would go for those who had supplied them as well, even—especially—if they were Governments who did not accept the proper international constraints.

It is not as if we are saying that progress towards multilateral disarmament is either undesirable or unattainable. The Government are right to point to the fact that under successive Governments—both the last Conservative Government and this Labour Administration—the United Kingdom has moved further than other nuclear power in reducing its nuclear capability. I was Secretary of State for Defence when we made the decision to get rid of our free-fall nuclear capability, to get rid of tactical nuclear weapons, and to make the first substantial reductions in the number of warheads available for our Trident system. That policy has been pursued.

I pay tribute to my right hon. Friend Mr. Mates, who said that the time had come to begin discussions with France on possible co-operation. Any threat to France or the United Kingdom in this regard must be a threat to both, given the geographical proximity of our two countries. When the Conservatives were in office we initiated informal discussions with the French Government to establish whether there were common thoughts on nuclear doctrine and on the way forward. My right hon. Friend made some imaginative proposals in suggesting that this might be the time at which to take those discussions further.

The Government deserve the House's support not because this decision will be irreversible, but because it gives a clear indication of our national intent.

Britain is a nuclear power, and has been a nuclear power for 50 years. We became a nuclear power at the end of the last war when we faced a threat from the then Soviet Union, and the development of the uncertainty of the cold war emphasised that threat. Fortunately the cold war has passed into the history books, but I agree with Sir Malcolm Rifkind that, given the way in which Russia has developed and is developing, there is no certainty that we can be secure in our relations with that country.

Now we are faced with new dangers and new threats from international terrorism and potential rogue states that would seek to undermine international security by sponsoring acts of terrorism, which could involve dirty bombs and nuclear weapons. In 1956, who would have predicted that in 2007 countries such as North Korea, India and Pakistan would have a nuclear capability, or that Iran would have nuclear ambitions? Now, in 2007, who can predict with any certainty the threats and challenges that this country, and indeed the international community, will face in 2024? That inability to predict the future means that scrapping the United Kingdom's independent nuclear deterrent would be a grave mistake, not just for this generation but for future generations.

The White Paper sets out three possible scenarios. We might face the re-emergence of a strategic nuclear threat, we might face the emergence of a new nuclear threat, or we might face the deliberate equipping of terrorist groups with nuclear weapons by a state sponsor. Each of those scenarios might seem too terrible to imagine, but sadly any one of them is possible, and it is for that reason that we must retain our nuclear deterrent.

Those who say that the way forward is merely to give up nuclear weapons must prove that we would not become a soft target for state-sponsored terrorism, or for others who seek to threaten us. I know that, in truth, it is not possible to prove that. While I appreciate the arguments that are advanced, I think it is naïve to suggest that if we gave up our nuclear deterrent, states with nuclear ambitions would follow our example. That is not the real world. Life is not like that; would that it were.

By making the decision to maintain our deterrent system beyond the life of the Vanguards with a new generation of ballistic missile-carrying submarines and extending the life of the Trident D5 missiles, we are renewing the insurance policy that we have had since the end of the war to protect us against those would threaten our security. Would any householder faced with the uncertain prospects of storms and other bad weather not make sure that he or she had a proper insurance policy? In an unpredictable and uncertain world, that has to be right for us.

As all the attention has been focused on the renewal of Trident, it is easy to overlook the fact that the White Paper also commits us to a further 20 per cent. cut in operationally available warheads. That is a good step forward that should be welcomed by all Members. For all the uproar over the renewal of our nuclear submarines, there is a clear commitment from this Government that any nuclear deterrent should be sensible and set at the minimum level necessary for the future defence needs of the United Kingdom.

Some might say that we can put off making this decision. That is wrong and lacks political courage. When I look at the Members representing the Liberal Democrats, I wonder where is the party of Gladstone and Lloyd George—the party that had the conviction and moral courage to take the decisions of the day and not run away from them. It will take an estimated 17 years to design, build and fully deploy a new submarine. A delay in making a decision would mean that there might be a period when there is a substantial gap in the possession of our deterrent. In what is a rapidly changing world, that is a risk, and we can ill afford to take it.

Attention has been drawn to the cost of the nuclear deterrent, and I am sure that that will be referred to again in other contributions. Indeed, it is right to draw attention to the cost of the Trident replacement. The capital cost of replacing the submarines and extending the life of the missiles is estimated to be £15 billion to £20 billion over 15 years. I agree that that is a massive cost, but if history teaches us anything it is that our freedom is not bought cheaply. There is a cost to preserving our way of life. I, for one, would prefer that we defend our freedom by deploying this deterrent than by sending millions of our young men to the killing fields of war, as we did twice in the last century.

There have been many fine speeches in this debate so far. The outstanding one was that of Mr. Ancram. In a previous incarnation, he was the Member for Edinburgh, South; he was beaten in that constituency by Nigel Griffiths. There is clearly something in the water in that constituency that gives people profound good sense when considering the issue we are debating.

Way back in the 1980s when the right hon. Jim Hacker was the Prime Minister, he developed a "grand design", which was to get rid of Trident and to invest the money in conventional forces and make the United Kingdom a safer and happier place. He was dissuaded from that course of action by Sir Humphrey, who in doing so was eventually forced to say that the ultimate reason for having Trident was that it was a Rolls-Royce nuclear system and that Britain deserved the best. Even thus far in this debate, I have detected that there is still that underlying argument about Britain deserving the best, because I think that ultimately this argument is about not deterrence, but Britain's place in the world. It is about virility and vanity, aspiring still to that superpower status, and saying, "We need a submarine platform, ultra-ballistic missile system, and Trident is still the best, so that's the one that Britain should have."

The Foreign Secretary tells us that that system amounts to only 1 per cent. of the nuclear weapons in the world and that we are negotiating that away to virtually nothing. In fact there are, according to the Foreign Secretary, so few warheads left in the Trident system that I sometimes wonder why on earth we have it in the first place. Perhaps we should follow Saddam Hussein's example and merely pretend that we have a nuclear deterrent. Perhaps we could have a virtual nuclear deterrent in order to have deterrence. The destructive force of the real Trident system—the destructive force that is still available—is awe-inspiring and deadly, and, as several Members have said, when we think about it possibly being used, that force is calamitous.

In the 1980s, many eloquent speeches were made by Members on this matter. I was particularly struck by the current Chancellor's contribution of 19 June 1984. In a debate similar to this one, he said:

"The dominant theme of this debate has been the concern expressed by hon. Members about the escalating cost of the Trident programme, a project which is unacceptably expensive, economically wasteful and militarily unsound. It is a project which, while escalating the risks of nuclear war, puts at risk the integrity of our conventional defences."—[ Hansard, 19 June 1984; Vol. 62, c. 188.]

Anybody in politics is entitled to change their mind—I have even done it once or twice myself—but I find it extraordinary that people could be against Trident when we faced the real and present danger of the might of the Soviet Union, yet for Trident when we face the potential might of North Korea. That is an extraordinary change of position to adopt. The situation was brilliantly summed up by Mr. George, the former Chairman of the Defence Committee. He revealed to us that he had been speaking "tosh", as he put it, back then. I am bound to think that he did not just speak tosh in the past—he is quite capable of speaking it now and well into the future. There has been an incredible volte-face.

I want to speak about civil society in Scotland. Members will recall that Scotland is, after all, to be the scene of the deployment of this new weapons system for the next 50 years, so what the people of Scotland think about it might be of some interest and concern to the House. It is not just that 80 per cent. of people oppose it; throughout Scottish civic society, people are pointing out, led by the Scottish Trades Union Congress, that it is unacceptable. Some Labour MSPs make the mistake of saying that there will be a jobs boost. They claim that 11,000 jobs will be created, but unfortunately, parliamentary answers in this House reveal that the figure is 1,300. The cost works out at £5 million a job. As the Scottish TUC has pointed out, the alternative cost is the many thousands of jobs anywhere in the public sector that could be generated by such a figure.

However, there are not just economic arguments but moral arguments, too. Scotland's Cardinal, Keith O'Brien, has written to me enclosing a statement not just from the Catholic Church in Scotland, but from all the Christian Churches in Scotland: the Church of Scotland, the Quakers, the United Free Church, the United Reform Church, and the Scottish Episcopal Church. Talking about the Churches coming together to make such a statement, our Cardinal said:

"I think you would be right in saying in your own statement to Parliament that this is a unique even in the history of the Christian Churches in Scotland".

The Churches' statement is a fine one. I will read just two points from what the Churches said:

"In April 2006 the Catholic Bishops of Scotland called for Trident not to be replaced but...decommissioned."

The General Assembly of the Church of Scotland said:

"To replace Trident would represent a further announcement to the world that safety and security can only be achieved by threatening mass destruction; this is to encourage others to believe the same, and thus to hasten proliferation."

When people in this House say that there is no possibility that Iran or North Korea—or even the French—would respond to our renunciation of nuclear weapons by doing the same, they miss the point entirely. They miss the encouragement that will be given to proliferation if we go ahead and invest in a system for the next 50 years.

The Foreign Secretary, in referring to the remarks by Mohamed el-Baradei, seemed to give the impression that he was criticising only the United Kingdom in this regard. In the interest of accuracy, I quote what he actually said:

"Nuclear feeds nuclear. As long as certain countries"— all nuclear countries—

"continue to insist on the indispensable character of nuclear weapons for their security, other countries will want to procure them."

That is his argument.

The point is well made, and of course, it is not just Mohamed el-Baradei; Mikhail Gorbachev and Hans Blix have made very similar arguments, pointing out the dangers in terms of proliferation if the Government go ahead with this disastrous course of action.

The Foreign Secretary repeated what can only be described as the smear made by the Defence Secretary on television a few days ago. She suggested that Mohamed el-Baradei is somehow conspiring against Britain, and that it is unfair that he is commenting only on Trident and not on the other countries. We should remember that this is someone in whom the world is investing so much hope in preventing the proliferation of nuclear weapons. Surely this House should have the decency to pay some attention to the points of view that he is expressing. Incidentally, Hans Blix would have no problem whatever in discovering weapons of mass destruction in Scotland—on the River Clyde.

The Prime Minister says that the country is in grave danger. In fact, he keeps coming to Scotland to try to avert that danger—of Scottish independence. He has said that we are really serious about Scottish independence.

Will the hon. Gentleman give way?

I know that I am on the subject of seriousness, but I cannot resist the hon. Gentleman.

In the hon. Gentleman's usual satirical style, he pokes fun at every party that disagrees with him. In the last few minutes of his contribution, can he give us just a slight insight into what the SNP's defence policy would be?

I poke fun because there has been so much inconsistency in this debate, but even the hon. Gentleman would have to concede that the Scottish National party has been rock-solid consistent in its opposition to nuclear weapons throughout the history both of the party and of nuclear weapons.

In a world of 200 nations, 10 of which are nuclear powers and 190 of which are not, I would like an independent Scotland to be one of the 190, not one of the 10. The desultory argument that has been made is that unless we have nuclear weapons, we will be threatened. If the former Foreign Secretary, Sir Malcolm Rifkind, for whom I have great respect, had been the Defence Minister of the state of Iran, he could have put forward exactly the same argument: "We will be threatened unless we acquire a nuclear deterrent." It was said earlier by the Conservative Front-Bench spokesman that we should understand why the state of Israel requires nuclear weapons, but that is against every international agreement. Every country in the world could say, "We are under threat, we require nuclear weapons." The path on which that argument would set us is not to 10 countries having nuclear weapons, but—given their declining cost—to 100 or 150 having nuclear weapons. Do we really think that in those circumstances, any form of international agreement would stop a nuclear exchange?

It is really important that we try to exert whatever moral force we can towards the de-escalation of the nuclear threat. My point about the Prime Minister is that he said that there was a serious risk of Scottish independence. We believe that it is a fantastic opportunity, but if it is a serious risk, why do people want to put their nuclear weapons in a country that could shortly be independent? Is that really a risk that this House would like to take? I can tell the House that this is something up with which the people of Scotland will not put. Surely in those circumstances the safe course of action for the right hon. and learned Member for Kensington and Chelsea, now that he no longer sits for a Scottish constituency, would be to advocate that the replacement of the weapons system be sited on the River Thames, as opposed to the River Clyde.

Unless people can accept the risk in their own community and unless they can recognise that arguments for proliferation could apply to every country in the world, they will take us down the road not of mutually assured destruction, but of certain destruction, from the proliferation of nuclear weapons.

One cannot but draw encouragement from the fact that when occupants of both Front Benches come together in agreement there must be a good deal to be said for the opposite argument. So it is today. Like others, I do not believe that the Government have adequately or convincingly answered certain fundamental questions about renewing Trident, in particular its true cost, why a decision has to be taken now, whom it is meant to deter, and how it is genuinely compatible with non-proliferation.

Nor has there been a real opportunity to obtain fuller answers, because the process of consultation has been unjustifiably squeezed. There is an unmistakable sense in this latest exercise that both Parliament and the electorate are being bounced into this decision. I still believe that there is a strong case for further and fuller consultation of the electorate before such a momentous decision—which will cost taxpayers some 6 per cent. of GDP—is made.

The argument against renewal of Trident is extremely strong—

I think that my right hon. Friend meant 6 per cent. of the defence budget, not 6 per cent. of GDP. He may wish to amend the record.

No, I am referring to a cost of £75 billion—I shall discuss that further in a moment—which is roughly 6 per cent. of GDP. It is substantially higher as a proportion of the defence budget.

The post-cold war environment today is, of course, utterly different from 20 years ago and even the Ministry of Defence cannot plausibly identify an enemy—either currently or in future—against whom Trident might be necessary. I will come on in a few moments to the uncertainties of future events in the world and to what I believe to be the central issue of the debate.

My right hon. Friend mentioned his concern for the views of the electorate as against those of the House. Should he be successful and become the leader of our party in the autumn—[Hon. Members: "Hear, hear!"]—will he give an undertaking to reverse the party's policy of multilateral nuclear disarmament. If he fails to do so, will he abide by party policy?

I am pleased to see the widespread support that I receive—at least on one side of the House! I would certainly reopen this decision, as I believe that consultation has not been adequate. I would like to see a consultation along the lines of the first strategic defence review, which lasted for a year—1997 to 98, I believe—as nothing less would be right now. On that basis, and taking account of all the relevant options—they have not all been put sufficiently to the electorate—I believe that we should have a further two-day parliamentary debate. I give an absolute commitment that I would abide by the result. I believe that it would provide a fresh and genuine mandate.

If we are talking about the threats that our country faces today, we know that they are primarily terrorism, climate change and long-term energy security—against all of which, of course, nuclear weapons are useless. Furthermore, this is not an independent British nuclear deterrent, since the platform, the delivery system, the warheads, and even the onshore support, are all dependent on our US relationship. The Trident II D5 missiles are leased from the US missile pool under a system known in the trade as "rent a rocket".

Will the right hon. Gentleman give way?

No, I am not giving way again.

Not only are the warheads designed by the US, but several crucial components without which the system could not work are manufactured in the US, and the system is also reliant on US software for all aspects of targeting. What is even more serious in respect of our over-dependence on the US is that the US provides this kit to us not because they believe that we are necessary to the defence of the west, but because it makes us subservient to US foreign policy. We have already seen that with Iraq and Lebanon, and could well see it again over Iran. I, for one, believe that that is a political price far too high to pay for the next 30 or 40 years.

The enormous cost, of a distinctly vague and uncertain role, has already been touched on. Even MOD officials have admitted that the lifetime costs of Trident renewal could be two to three times the £15 billion to £20 billion figures mentioned in the White Paper—and that covers only the initial building of the system. That is close to the £75 billion I mentioned earlier, which is the amount arrived at by the independent think-tank, the British American Security Information Council.

Figures of that magnitude starkly expose the recently highlighted funding gap within the MOD's current procurement plans beyond 2012. That includes some major equipment procurement such as two carriers, the joint strike fighters and possibly a third tranche of Typhoon Eurofighters. The budget means that we cannot have both those and Trident together: we have to make a choice. I would submit that those systems are likely to be far more relevant and valuable for our defence capability in future than nuclear weapons.

The truth is that none of our wars have been won with nuclear weapons and none of our enemies deterred by them. General Galtieri was not deterred from seizing the Falklands, even though we had nuclear weapons and he did not. The US had nuclear weapons, but that did not prevent them from being defeated in Vietnam and now in Iraq. The French had nuclear weapons, but that did not prevent them from being chased out of Indo-China and Algeria. Israel, of course, had nuclear weapons, but that did not prevent them from being evicted from Lebanon by Hezbollah in 2000 and again last year.

The only argument that the Government and the Opposition fall back on is that we might one day in the hypothetical future, in a worst-case scenario, face a rogue state. However, the logic of the "rogue state" argument, as has rightly been pointed out, is that if we need nuclear weapons against such an eventuality, so does everybody else—not just Iran but the 40 or so technologically advanced states that are already capable of producing nuclear weapons. The question that then arises, which we need to answer tonight, is whether British will really be a safer place if we trigger a spate of nuclear proliferation across the world leading to regional arms races and a world of 40 or more nuclear states. Far from the risk of nuclear war being diminished, I submit that it is far more likely to be enhanced—whether from miscalculation, terrorist acquisition or another cause.

There is no question but that renewing Trident will undermine the spirit of the non-proliferation treaty. There has been a lot of discussion about that, but let us be clear that the deal in that treaty is that the non-nuclear countries will not seek nuclear weapons, on condition that nuclear countries move steadily and in good faith to full—I emphasise the word "full"—nuclear disarmament. If we decide to renew Trident, that will be a clear message that the nuclear states—although I entirely concede that they are making some important reductions in their nuclear weaponry—are nevertheless still baulking at the end process of nuclear disarmament. That is all too likely in time to lead to a steady growth of further proliferation among a whole swathe of non-nuclear states. Ultimately, that could prove unstoppable.

No one—certainly not me—supports the view that Britain can unilaterally bring about nuclear disarmament world wide. That is a complete canard. Of course we cannot, but there is a window of opportunity. Most experts agree that there is no requirement for an immediate decision to be taken on this issue before at least 2014. That gives us an invaluable opportunity to take the lead, which is what I think we should do, in trying to set up a multinational, multilateral nuclear disarmament conference embracing not only the existing nuclear states but also the non-nuclear states that might be tempted to go down this route, in order to give a decisive multilateral push to halting nuclear proliferation.

Will the right hon. Gentleman give way?

No, I do not have the time. I believe that what I have described is a much better route to a safer world, and we are in pole position to take a global lead.

Finally, let us not forget that over the past generation more nations have given up nuclear weapons than have developed them. None of those countries—Brazil, Argentina, Ukraine, other former Soviet states and South Africa—regard themselves as less safe than they were before—

Order. The right hon. Gentleman's time is up.

It is good to follow a few excellent speeches in the debate. I particularly compliment Mr. Ancram who, as Mr. Salmond said, was the Member for Edinburgh, South before Nigel Griffiths, who has made his resignation speech. Dr. Strang was of very much the same opinion, and I am sure that Mark Lazarowicz will also oppose the Government tonight, as will I as the Member for Edinburgh, West. There may be something in the water.

Tonight's decision on Trident will haunt the House if we get it wrong. If anyone is still wondering why there is a rush to make a decision now, the answer is clear. The Americans are extending the life of their D5 Trident missiles and they want answers in 2007. They need to know whether we are willing to join them. There is no pressing military, political, technical or other reason to make the decision now. The only reason we are being bounced into this decision is the current Prime Minister and his wish to leave the country's hands tied long after he has gone. It is not the submarines that are reaching the end of their shelf life; it is the Prime Minister.

Will the hon. Gentleman explain why, months before the Prime Minister made his statement, the Chancellor of the Exchequer said that he believed that we should keep the nuclear deterrent not only in the present Parliament, but in the long-term future, and why the defence White Paper, as long ago as 2003, made it abundantly clear that the decision would have to be taken in this Parliament? That was nothing to do with the Prime Minister leaving office.

I am sure that the Chancellor would like to see the dirty deed done for him before he comes to office. In the Government's White Paper we are told that only the Prime Minister can push the nuclear button. That is of little comfort to many inside and outside the House.

I am glad to be called to speak in the debate, because not only do I feel strongly about this issue, but I know that many of my constituents feel the same way. Many have written to me and some have asked for copies of the Government's document on the future of the United Kingdom's nuclear deterrent. Others have written on behalf of larger groups and organisations, for example, the Churches.

Will the hon. Gentleman give way?

No, I am just going to give way once.

It has been interesting to hear those views and I have read and answered every letter and e-mail. There has been a steady flow. It would be good to give a few examples of people who wrote to ask me to support the Government's position, but there was not one. One letter was from an Edinburgh city councillor, who asked me to oppose the Government tonight—he asked for my support and he is a Labour councillor.

I have said on many occasions that there are two threats that we must face up to: global warming and terrorism. Nuclear weapons, as has been said earlier, are useless against both. There has been much talk about the uncertainty of the future. Why, then, are the Government so convinced that, in the face of that uncertainty, a nuclear arsenal is the answer? If deterrence is working, will someone explain exactly which nations are being deterred? Which country is so mad that it would launch a nuclear strike on us and, at the same time, so reasonable that it would be stopped from doing so by our possession of these weapons?

The potential use of the weapons is also a key issue. Page 14 of the Government's White Paper refers to the fact that the Government believe that the use of the weapons would not be unlawful and that the threshold for legitimate use would be high. Well, that might be good enough for some, but it provides little comfort to me or many outside this place. Combined with the statement that

"we will not rule...out the first use of nuclear weapons" it means that the weapons might be used either in a pre-emptive strike, possibly to kill tens of thousands of innocent civilians, or in retaliation, again to kill tens of thousands of innocent civilians. Either way, it would be a disaster and immoral.

Relying on intelligence to launch that first strike is asking others to do the same if they feel under threat from us. Giving everyone a gun does not make our streets a safer place to live in. We in this country are members of a very small, exclusive club of nuclear powers. A very few countries want to join, but most countries are not members and do not want to join. Most European countries do not possess nuclear weapons. If it is good enough for Spain, Italy, Germany, Sweden and Norway, it should be good enough for us.

Page 22 of the White Paper describes the Government's preference for an invulnerable and undetectable system. That is the key component of the entire system. However, the proposal is also based on the assumption that the technology to detect the position of submarines at sea will not be developed soon. When that technology is more accurate and widespread, the position of the submarines will not be a secret at all. Having all the missiles in a submarine whose position is known makes that submarine a target for every terrorist and rogue state that we can think of.

If proliferation is a problem, what moral justification is there to say that we are entitled to possess nuclear weapons, but others, such as North Korea and Iran, are not? Members do not have to take my word for it, they can listen to what Dr. Hans Blix had to say. I remember well when the House was presented with the evidence in relation to Iraq. When he challenged that dodgy dossier, which claimed that Saddam Hussein had nuclear weapons, the Prime Minister should have listened to him, and we should listen to him now. He has said that modernising Britain's arsenal will put the non-proliferation treaty under strain and will increase the likelihood that non-nuclear states such as Iran will want to join that nuclear club. The chairman of the Weapons of Mass Destruction Commission knows what he is talking about and we should heed his words.

What could be done with the money saved if Trident were not replaced? Our priorities should be protecting the planet, building a first-class health and education service, investing in our children's future and looking after the vulnerable in society. Further afield, the wars that we should be waging with those resources are the war against poverty and hunger in Africa and beyond and the battle against AIDS, tuberculosis and malaria, which have killed more than 6 million people this year. We should be caring for the victims of war, not creating more. We should be helping orphans, those trapped in refugee camps in Darfur and the millions who do not have access to clean drinking water.

I will be voting against the Government's plans to replace Trident. Once again, the Prime Minister will have the support of much of the Conservative party, which is no surprise as many Conservative Members see him as their natural leader. We have the opportunity to look forward and raise our gaze above the horizon. Those who want to build a future based on the threat of weapons of mass destruction will not only make the world a more dangerous place, but miss a golden opportunity to leave behind an age in which mankind has spent much time developing weapons with the capacity to destroy all life on the planet many times over. Saying that the best that we can think of is to spend billions of pounds on a weapon of mass destruction is an admission of failure. We should be offering the British public something better. Nuclear weapons were developed to deal with the threat of the last century. It is time to move on and consign them to history.

There is an anachronistic feel about the debate—it is like a debate from another era. Time and the world have moved on, and we should move on as well.

In the modern world, new fears have emerged that are based on new threats. Those fears and menaces demand new responses. If we do not recognise that the world has changed and simply respond to new fears with old solutions, we not only fail to address the real threats, but we risk contributing to setting in train a process of global instability and nuclear proliferation, which has the potential of spiralling out of all control.

The old way of responding to fear was a form of international trench warfare. Armed to the teeth with nuclear weapons and clinging to each other in aggressive alliances for mutual protection, we sat tight in the trench monitoring the enemy's every move. In a bipolar world, the enemy was visible, obvious and predictable. The new threats are unpredictable and often barely visible. Sometimes the threats come from other states, but they are more likely to come from small, invisible and unpredictable terrorist groups. In the modern world, new techniques are used to deal with states and terrorism.

Does my hon. Friend accept that the biggest threats to this country come from terrorism and climate change, and that the investment of tens of billions of pounds in a nuclear arsenal and weapons of mass destruction will not help a bit to tackle those two important issues?

It is irrefutable that if we look into the 21st century, the major threats are exactly those that my hon. Friend identifies. I fully concur that this investment will not contribute to tackling those threats.

If a state is the cause of international or regional tension, the international community is becoming increasingly adept at engaging in negotiated solutions to bring such wayward states into line. The demonstration of a united approach through global institutions such as the UN and the use of economic and diplomatic isolation have become an effective means of resolving individual state-led threats. If diplomatic and economic isolation have not worked, the threat, or actual use, of conventional forces in the last resort has been deployed. That is the proportionate response in the modern setting.

The argument put forward to justify a new nuclear weapons system is that we cannot predict what threat will emerge in the future, or what rogue state will arrive on the scene to threaten us with nuclear attack. In reality, we can and we do. Rogue states do not just develop on the world state unannounced; they develop over time. Ironically, it is often the British and United States Governments that have nurtured and armed them, and assisted in placing in political power a brutal regime to rule them. However, that is another story.

Tackling rogue states effectively in the future will not rest on the deterrent effect of the nuclear arsenal of an individual country such as Britain. The concept of Britain's independent nuclear deterrent looks even more preposterous now than it did four decades ago. Any strategy to deal with an errant state will, of necessity, be dependent on international co-operation. It will be based on the early identification of possible conflicts and the promotion of conflict prevention and conflict resolution.

Even if, in a transitional phase, there was an underlying role for the deterrent effect of nuclear weapons, it would not be based on the fiction of an independent British deterrent, but on an internationally controlled deterrent, possibly under UN determination. Indeed, bringing nuclear weapons under international decision making is the obvious first step towards their eventual elimination. If the only remaining argument for Britain's retention of Trident and our development of new nuclear capabilities is the unpredictability of the emergence of threat states, I point out that any workable rogue-state strategy has to be based on extensive dialogue with our international partners and on the securing of a new international agreement. If we decide to replace Trident today, we not only undermine our commitment to nuclear non-proliferation, but pre-empt any attempt to secure a new international settlement.

In this new world, we have new responsibilities. The prime task of any state is to protect its citizens, but we are now formally members of much wider communities and we have a responsibility to work in co-operation with the members of those communities. Individual nuclear solutions, especially in Europe, are as outmoded in the 21st century as gunboat diplomacy was in the late 20th century. The onus is on us to consult extensively with our European partners about the future defence of Europe and the role that Britain should play.

Political attitudes in the US are changing rapidly, too, and there needs to be a wider discussion with all political parties in the US about the future of nuclear weapons. As for the UN, given the role that Britain played in developing and signing the nuclear non-proliferation treaty, if we are to maintain any credibility Britain should at the very least lead an honest debate on the progress that has been made in implementing that treaty before any decision is taken on Trident replacement.

Does the hon. Gentleman think that the world would be a safer place if all western democracies unilaterally gave up all nuclear weapons?

I believe that it would be a more dangerous place if we invested in a new phase of nuclear development; it is as simple as that. Our job is to promote security and peace, not to undermine it. There is a feeling in our country that the Prime Minister has avoided the meaningful, widespread consultation and debate that a decision of this magnitude deserves. Complaints have been made in the House today about decisions being bounced. There are allegations of a done deal with President Bush and the pre-emption of the parliamentary vote. That does not convey the impression that the country is at ease with the decision-making process that the Labour leadership has fixed on for this critical policy decision, and that is no way to determine a fundamental policy that will affect the lives of the next generation.

Clear choices face our country: do we come into the modern world and recognise that the world and its challenges have changed, or do we sink back into the imagined comfort of the fiction of a British independent nuclear deterrent? The £20 billion, or whatever the escalating figure for the Trident replacement is, will buy us a very expensive comfort blanket that will have an effect on our conventional forces. Do we, out of post-imperial vanity, try to maintain our place at the international high table by ploughing much-needed resources into weapons of mass destruction, or do we appreciate the role that we could play alongside our European partners as a leading peacemaker, a conflict preventer and a conflict resolver?

The debate is not just about Trident—it is about how we see the future of our country. It is about whether we have the courage and honesty to come to terms with the 21st century. Gone are the days of empire, and gone is our vainglorious strutting on the world scene as a military and nuclear power. Instead, we can shape a progressive future for our country as a force for peace in the world. We can lead the world in the debate on how we can progressively eradicate the threat of nuclear war. Today's debate could be the start of that process, but if we precipitously embrace Trident's replacement, we could stall that hope for a generation. I choose hope, and that is why I will vote against the Government and the replacement of Trident tonight.

At the height of the second world war, my parents' home in Plymouth was blitzed by the Nazi dictatorship with conventional weapons. In 1947, we moved to Salisbury, which was a garrison city. During my schooldays, I vividly remember the invasion of Hungary, the days of Checkpoint Charlie and the terror—always hanging over us—of the cold war, growing to the time of the Bay of Pigs. All that has conditioned the brief remarks I am about to make.

I want to address the issue of what we think we are deterring and what we think we are defending. However, it is important to recognise that the Government have taken an important step forward by holding the debate at all. On both sides, we have seen responsible government and responsible opposition operating in the best interests of our country.

We need a decision on the issue now. I stand by the three reports that the Defence Committee, of which I am a member, has taken a year to prepare. They lead me to make various conclusions. I regret that the Government did not participate in the Committee's first report, because that meant they failed to consider publicly the threats the UK faces and how they might evolve in the future, which the House should consider.

Our second report considered the consequences for the UK manufacturing and skills base of abandoning the nuclear deterrent. We concluded that the industrial and social consequences should not be the main factor in the decision on the future of Trident. The third report, published last week, looked at the timing of the decisions on our deterrent, its scale and the legal and treaty aspects.

At present, I am the only Member of the House who is a member of the General Synod of the Church of England, and I think it is extremely important that we should listen to the message sent by the established Church. It is because it is the established Church that it should make its views clear. The Church of England did not simply say that it was opposed to any kind of nuclear deterrent. The Archbishop of Canterbury said:

"I believe that the least a Christian body ought to do in these circumstances is to issue the strongest possible warnings and discouragements to our Government."

He made a strong moral case against nuclear weapons in general. Of course, his views are not unanimous. On 11 October, the Bishop of Liverpool said:

"Nuclear knowledge can't be unlearnt, its evil genie of weaponry can't be sucked back into the test tube. It's a fact of the modern world, as factual as those sinister imaginations that can not only contemplate human terror but actually inflict it."

The Bishop of Rochester, writing in The Sunday Telegraph under the heading "I believe in Trident, and using it if necessary", said:

"The task of the Churches...is to resource the debate by setting out the moral criteria which need attention rather than trying to make Government policy from the sidelines."

I concur absolutely. Last week, I took part in a debate in Synod where I made it clear that I believe we should proceed with Trident.

We need to consider that there will be new technologies in the future. There will be new weapons and they might be more morally acceptable, but it is important to recognise that morality is not the exclusive preserve of protesters, whether outside the gates of Parliament, hanging over the river, outside the gates of No. 10, or outside Faslane, Devonport or Aldermaston. Most people, including most Christians, reject the pacifist morality that says it would be better to be subjugated by superior military power and lose our freedoms than to possess nuclear weapons, on the grounds that no dictatorship lasts for ever and our moral judgment would be intact—even if we were in chains or dead.

At this time of nuclear proliferation and global terrorism, there is no evidence that disarmament by the UK would have the slightest influence on people who wish us harm. I was elected to Parliament to represent about 118,000 people, many thousands of them in uniform or working as civilians in the Ministry of Defence. Tonight, all Members will have to decide on the balance of moral arguments, but I will not risk the security and freedom of my constituents and of our nation by voting not to renew a nuclear deterrent.

France has been much mentioned, which is important. Only three weeks ago, I was in Paris as a member of the Defence Committee. We listened and talked to representatives from the French Defence Ministry and the Assemblée Nationale. We were briefed by the President's defence adviser in the Élysée and I raised various issues, including possible collaboration over nuclear submarines and aircraft carriers. However, I have to tell the House that my impression was that the French were longing for us to give up our nuclear deterrent, and I cannot help recalling that the last time the destiny of the United Kingdom was in the hands of the French, William the Conqueror paid us a visit.

Finally, the community in the west needs to be quite clear what this is all about and what we are defending: not our territory from physical invasion, but our western tradition of culture, civilisation and democracy, at the heart of which is Christianity. What is at stake is the proportionate force that we should possess to defend those values of humanity, well-being, tolerance, freedom of worship for every religion, justice, the rule of law and freedom itself. Those are the issues that we are debating tonight and I am in no doubt at all that the risk should not be taken of abandoning the defence of those values.

Many right hon. and hon. Members tonight have acknowledged that the cold war is over, but the White Paper on the future of Trident is still rooted in cold war thinking. It makes no real analysis of the future role of the US-led and nuclear-armed NATO alliance of which we are a part, nor of the new Europe in which we live. It is a mass of assertions with no attempt to examine how best to approach security in a world where climate change and competition for resources and markets will be paramount.

Instead, we are given three scenarios for threats that the White Paper tells us can be countered only by Britain maintaining its nuclear weapons system until 2050. We are told that a major nuclear power, presumably Russia, may re-emerge to threaten us. Now Russia may be an imperfect democracy, but why should the Russians, who have everything to gain from a more united Europe, specifically aim their nuclear weapons at Britain? Whatever the potential conflicts over oil, does anyone really believe that nuclear weapons could be used to settle any such future conflicts?

The White Paper goes on to pose a second threat: new states acquiring nuclear weapons and threatening our vital interests. Iran is the country most often cited. Embroiled as that country is in middle eastern politics, with a nuclear-armed Israel on one side and a nuclear-armed Pakistan on the other, it is impossible to understand why Iran would want to target its nuclear weapon, if it acquired them, specifically at the United Kingdom. I am the last person to support Iran in its endeavours, but it is inescapable that if we argue that we need nuclear weapons to protect us against future threats, so can Iran. As the head of the International Atomic Energy Agency, Mohammed El Baradei, recently warned, a decision now to renew Trident sends exactly the wrong message to those countries that we would wish to deter from the acquisition of nuclear weapons.

The third threat posed in the White Paper is that countries might sponsor nuclear terrorism from their soil. This, frankly, is the most preposterous assertion of nuclear deterrence. Do we really believe that the dirty bomb in the suitcase is going to have a survivable country-of-origin label on it? We all know that suicidal terrorists cannot be deterred by nuclear weapons and they know that it would be impossible immediately to identify a sponsoring state so as to justify nuclear retaliation.

Let us however suspend disbelief for a moment and accept that all these threats can be deterred only by nuclear weapons. Why then should Britain be uniquely targeted by Iran, North Korea or any other state? The White Paper asserts continually the deterrent value of British nuclear weapons without advancing a single plausible threat scenario. But it is not even that simple. As the Prime Minister wrote to George Bush last December, in the letter to which my hon. Friend Jon Trickett referred, the new British nuclear weapons coming into service in 20 years' time would be assigned to NATO, as now. With the end of the cold war and an expanded Europe, do we really think that we would get agreement from all our allies to use British weapons of mass destruction? Or that the US would not intervene if Britain wanted to act independently but that did not suit the US? It is just not credible.

Will the hon. Lady give way?

No, I am sorry; I would be taking up the time of others. The hon. Gentleman and I have debated many times.

We must ask what kind of world we want to live in, and how best we can contribute to achieving it. The threats that we face today and that we will face in future are not UK-centric—they are global, and they require global solutions. International co-operation on climate change, world trade and technology transfer are vital if we are not to face climate catastrophe and a scramble for diminishing resources. International co-operation on terrorism, genocide and poverty reduction are vital if we are to reduce conflict and stem the mass migration of people.

Britain has made a huge contribution in all those spheres, but we have signally failed to place them in a coherent foreign and security policy. The renewal of Trident depends absolutely on US co-operation. It ties us into a US view of the world, when many of us—perhaps most of us—would prefer a looser relationship and a greater recognition of the security that we derive from our place in Europe. Planning to give up nuclear weapons is not the hopeless gesture that has been portrayed by many right hon. and hon. Members. It is what the vast majority of states that have become nuclear-free zones want us to do—states which have formed themselves into nuclear-free zones; states like South Africa and Ukraine, which gave up their nuclear weapons; states like Argentina and Brazil, which abandoned their programmes by mutual consent. The international community persuaded Libya to give up its nuclear weapons programmes; progress has been made on North Korea; and Iran remains under intense pressure. Negotiation is our only intelligent option.

At the 2000 non-proliferation treaty review, Britain made

"an unequivocal undertaking to accomplish the total elimination of nuclear weapons".

Tonight, however, we have been asked to spend billions of pounds and years of endeavour so that we can deploy new weapons of mass destruction to patrol the seas until 2050. We should begin, instead, to reconfigure our security policy by agreeing that Britain will become a non-nuclear weapons state by 2025. That would bolster demands that the US and Russia negotiate a new agreement to replace the strategic arms reduction treaty, and it would give us an opportunity to play an even more positive role in the multilateral negotiations that will be part of the 2010 review of the non-proliferation treaty.

Mr. Ancram referred to the credibility of deterrence. I very much concur with him, and I admired his speech. A weapons system is credible only if it can be used, and I have not heard any argument showing how Trident could be used to our advantage. I know the consequences of using it, however—thousands of innocent people would be vaporised; millions would die in agony; and radiation would persist for generations. The health and environmental consequences are incalculable: I have never been willing to be party to such a barbarous act, and I will not support my Government tonight.

I wish to make three points in the short time available tonight. First, the decision does not need to be made now, and the argument that it must is an effort to embarrass the Liberal Democrats and is not credible. The Prime Minister said at Prime Minister's Question Time that the next Parliament could revisit the decision, which makes it clear that the decision does not have to be made tonight. The case against making it today was adequately summarised in an editorial in today's Financial Times. The Prime Minister is trying to lock the Labour party into policies that he supports, and the Chancellor is suddenly trying to prove that he is tough on security by spinning on the back of a speech about the economy his support for a replacement for Trident, without any proper debate about Britain's foreign policy and its role in the world after the disastrous mistakes in Iraq.

Secondly, there is no argument in the White Paper, in the Prime Minister's introduction to the White Paper, or in the speech by the Conservative spokesman, that could not be reasonably made by Iran and many other countries. The greatest threat we face in the nuclear context is proliferation. The non-proliferation treaty is unravelling. The decision that we are asked to make before it needs to be made means that Britain will not consider how it can best contribute to driving forward and re-establishing the strength of the non-proliferation treaty, and is in danger of weakening it.

The United Kingdom has a nuclear weapon targeted at no one, with no one targeting a nuclear weapon at us. Iran is in an extremely unstable region, with Israeli nuclear weapons undoubtedly targeted at it. If the argument is made that the future is uncertain, what right does anyone have to say that Iran should not get a nuclear weapon? If Iran gets a weapon, Saudi Arabia will want one, as will Egypt, Turkey, Jordan and perhaps even the Gulf states, which have made some moves towards getting a capacity in nuclear technology. There will be very dangerous proliferation in the most unstable region in the world.

That is the real threat that the world faces and that we face, and it is being cast to one side by the blanket decision to replace our existing weapon in 20 years, rather than concentrating on how we in the UK could contribute to strengthening the non-proliferation treaty and preventing dangerous proliferation, particularly in the most dangerous region in the world.

The third reason why the UK should reconsider its approach to nuclear weapons is that they chain us into the role of US poodle. We acquire the weapons from the United States and we have to send them back to be repaired and serviced, so we can retain the weapons only if we are always on good terms with the US. That means that we do not have an independent foreign policy, as has been demonstrated so disastrously in Iraq. That has humiliated our country and helped to make the world more dangerous by dividing it more deeply and undermining international law.

I do not believe for a moment that we should seek to fall out with the United States. We have a long shared history, a common language and so on. However, every post-war Prime Minister apart from Edward Heath, bless him—because he was so focused on entrenching us in the European Union—has been obsessed with the special relationship as the centrepiece of our foreign policy. Why? It goes back to Britain losing an empire and failing to find a role. We are not the big power that we used to be, but we are best friends with the biggest power in the world, so if we can get a weapon from the US and stand alongside it, we are still important and powerful. That is an almost pathetic role to see for ourselves in the world. It is like the child who is frightened of others and therefore makes best friends with the biggest bully in the playground.

As has been said by other hon. Members, the biggest risk that we face is global warming, which could threaten the future of human civilisation. There is no question about that. I do not believe we will reach the international agreements that are needed to prevent that threat without establishing a much more equitable world order. Doing so should be the centrepiece of British foreign policy, seeking strong multilateral institutions, a much strengthened United Nations, much more equitable trade rules and so on, so that we can achieve the environmental agreements that we need to preserve the future of humanity.

Enormous threats are also posed by the growth of population that is coming. We are moving from a world population of 6 billion to 8 or 9 billion by 2030 to 2050, and 90 per cent. will be born in the poorest countries where the environment is under strain and states are weak. That threatens to bring not only terrible human suffering, but massive movements of population that will cause enormous instability and aggravation in the world.

Another major threat is the anger in the Muslim world about the injustice that is being suffered in the middle east. Instead of seeking to arm ourselves with a weapon because we fear that disorder, we should seek to unite with others to bring about a just settlement in the middle east. We say that we are committed to resolving the Israel-Palestinian conflict, but we always line up our policy with that of the United States, which does not act in that way. The situation is thereby constantly aggravated and the danger of large numbers of angry young people throughout the Muslim world concluding that the only way to resist state force is with non-state violence, which threatens the future of all of us, is growing and growing.

Lots of the speeches that have been made today have sought to re-run the old arguments about unilateral nuclear disarmament, but that is not what we are talking about. We are talking about whether we commit ourselves to replacing our weapon in 20 years' time or whether we could look for a strategy that uses our influence and our willingness to disarm to strengthen non-proliferation, with a stronger multilateral system, greater equity, more authority for the United Nations and a just settlement in the middle east.

What Britain needs is an independent foreign policy to make a real contribution in the world and to make up for the humiliation that we imposed on ourselves with our dreadful policy on Iraq. To decide to replace Trident in 20 years' time is to continue to tie us to that mistake and continue to humiliate our country.

Clare Short seemed to say at the beginning of her speech that the timing of this debate was intended to embarrass the Liberal Democrats and that there was no need to take the decision now. She then cited the Prime Minister's answer referring to the further decisions in the next Parliament as though that was evidence of that.

The whole point of taking the decision now is that we will not be able to make decisions in the next Parliament if we do not support the Government tonight. If we are to continue with the present deterrent, the submarines need to be renewed or replaced. Detailed design concept work needs to start now if we are to maintain continuous at-sea deterrence. By having the submarine continuously deployed, we do not inadvertently raise the threat threshold, which could happen if a submarine was deployed from standby. Constant deployment is also important in keeping crews at the highest level of professionalism.

The Defence Committee's report sets out the pros and cons on the timing issues, but the weight of the evidence set out in chapter 3 points clearly to the need to take a decision about the submarines now, given that 30 years is the safe and cost-effective limit of life extension and 17 years is the required period to do it. Our report also says that the Government deserve to be commended for exposing the proposal to public debate and decision in Parliament, which previous Governments have not done at this stage. That transparency is very much in keeping with one of the 13 steps that emerged from the 2000 non-proliferation treaty conference calling for just that. The decision that we face tonight to give the go-ahead to work on the detailed design concept is being taken at an earlier stage and more openly and fully than before.

Does my hon. Friend agree that the work force in my constituency at DML and at the dockyard would not accept the argument that the issue of the industrial skills base is specious? It is important that we take the decision now; otherwise, we will lose those skilled workers to the domestic sector, not the maritime industrial sector.

I accept my hon. Friend's argument and will go on to make it in more detail.

Those who argue that the decision can be taken at a later stage are simply wrong. They should be clear that by recommending delay they are putting at a very high risk the capacity to build boats in future, for all the reasons set out in the Defence Committee's fourth report on the skills base. In effect, those who support delay back the unilateralist something-for-nothing approach. If our capacity to build submarines falls apart, the idea that the Americans will sell us the boats is not at all credible, as the Defence Secretary told us in his evidence on 6 February. This relates to the skills needed to maintain the submarines and corresponds with what I have been told on visits to bases where that maintenance is performed. As soon as the design concept was made available for the Vanguard submarines, our US allies made it clear that we had to take ownership of them and understand them inside out. Only in that way can we have a deterrent that is independent and that we are capable of managing to the very highest of safety standards—an essential characteristic, as I am sure all hon. Members would agree, of a system with such awesome potential destructive force. If we want a deterrent, we need to decide to give the go-ahead now and to build it ourselves.

Why do we need the deterrent? The reason comes down to human behaviour. Optimists might believe that if we set an example, others will follow, but there is no evidence that that would happen if we were to give up our deterrent now. Iran and North Korea do not appear to be hanging around waiting for us to make a decision. Sadly, the world is becoming more uncertain in this respect, not less. When we ask people whether they would like to give up nuclear weapons and spend the money on something else, of course they say yes. However, when we ask whether we should do so before others do it, a clear majority say no.

Fundamentalists, dictators, tyrants and, yes, terrorists are all bullies, in my book. In democracies, there are all sorts of ways of checking the worst excesses, and the ultimate safety valve is the ability to change the people in power through the ballot box. Bullies, however, are best stood up to by those who know the difference between being assertive and being aggressive, and that is something that the UK does really well.

All hon. Members take pride in the role of our armed forces in peacekeeping and peace-making. Their role of standing up to some of the world's most aggressive bullies to create enough space for the bullied to regroup, to regain confidence and to assert their right to a better way of life—as in Bosnia, Kosovo, Sierra Leone and Afghanistan—is often more controversial. However, that is as much about our security as it is about theirs. These days not many of us are called on to put ourselves in harm's way to achieve such outcomes, but it is British men and women—and, increasingly, their Commonwealth and Gurkha colleagues—who tend to be at the forefront of taking such action on our behalf.

Our deterrent is deployed all the time, and it has given us in western Europe freedom from the kind of mass killing that two world wars brought in the first half of the 20th century. It also has a part to play in creating the context in which we use hard power to make that space for ourselves and others to do the peacekeeping, peace-making and stabilisation work. In the even more uncertain times ahead—in which state-sponsored terrorism might well be joined by tensions arising from population movements driven by climate change, drought and water shortages in particular, and by greater use of nuclear energy in the world—whatever we decide on nuclear energy, it is highly probable that the deterrent will have an increasingly clear role. With the emergence of new superpowers and their client states and interests, we must not risk falling hostage to blackmail in relation to their retained and emerging nuclear arsenals. Only a nuclear deterrent can deter nuclear threats.

I believe that retention gives us a more powerful hand in working for non-proliferation. We are the only permanent member of the Security Council to have reduced to one platform—the submarine—and we have only 1 per cent. of the world's nuclear weapons. Our seat on the Security Council certainly does not depend on our continuing to have a nuclear deterrent, but with it we can use our achievement of reaching a minimal deterrent to pull others in that direction. We should maintain the multilateralist position of seeking something for something, not something for nothing. The arguments are, at heart, not only simple but the same as they have always been: something for something, or something for nothing; multilateralism versus unilateralism.

For the reasons that I have set out, all the amendments tabled today—including the one that has been selected—would result in back-door unilateralism, even though people do not quite understand that. That would happen because of the delay, and because of the engendering of a lack of confidence in the industry and in the individuals who work in it. Unilateralists tell us that we can reconstitute the skills base or keep it on ice, but neither claim is true. Scientists and engineers who do this work at the cutting edge of science, along with those who design and make space ships, have skills that are literally in the realms of rocket science. They will not stick around in large enough numbers and complex teams to do anything less. People need look no further than the cost and time overruns on the Astute submarine programme to see the risks of letting the skills base fall apart.

I have spoken mostly of the submarine, but I also wanted to say that the Government have responded to the Select Committee's report, and to deal with the points of my hon. Friend Jon Trickett about the missile. Knowing the risks of letting the skill base fall apart, only those who believe in giving away something for nothing—unilateralists— should go on into the Aye Lobby on the amendment. Multilateralists cannot credibly share the same lobby with them.

The debate has been enormously serious, and I approach it with a degree of angst that I have detected in a number of other Members who have spoken.

I was struck by the contribution of my right hon. Friend Mr. Arbuthnot, whom one would expect to be one of the most robust cold warriors and supporters of Trident imaginable. However, he declared some real worries, although he ultimately concluded that renewing Trident was the right thing to do.

I also have huge respect for the contribution of my parliamentary neighbour and right hon. and learned Friend Mr. Ancram, a previous shadow Defence Secretary and Foreign Secretary, who none the less came to the conclusion that he would vote against the retention of Trident.

Until today, I took the view—the Whips are listening—that this was a matter of conscience rather than a matter for a whipped vote. Had I come to the relevant conclusion—the Whip on the Front Bench, my hon. Friend Andrew Rosindell raises his ears expectantly, and I assure him that I shall not rebel this evening—I would have been more than ready to rebel, because I believe that this is more than anything an issue of conscience. After all, the House's decision could result, perhaps long after all of us are dead, in a catastrophe that we would all do anything possible to avoid. I have therefore approached the matter with huge concern.

Having listened with great care to all the arguments made today and during the run-up to the debate, I was initially struck by the notion that if we did not spend all this money on Trident we could spend it on conventional warfare. As I represent a constituency that has a number of defence bases, that argument was attractive at one stage. I have been convinced, however, by the argument advanced by the Secretary of State and the White Paper that the two pockets are entirely separate, and that spending on Trident will not affect the defence budget. The defence budget is too low anyway: it should be higher, and we should spend more on our conventional weapons. Whether or not we have Trident, that argument will not be affected.

I admire the idealism of the traditional CND argument, which a number of Members have advanced today. There have always been people who are ready to say, "I am a pacifist. I hate all forms of warfare, all arms, land mines, nuclear weapons and anything to do with armaments. I would abolish it." That idealism does not, however, appeal to me personally. We would certainly have done less well in the first world war had we abandoned our armaments in the run-up to it, as we did, to some degree, in the run-up to the second world war. I suspect that the catastrophe of 1939-45 would have been less bad had we rearmed sooner and listened to Winston Churchill among others.

I am one of those who are convinced that we won the cold war not because of the activities of CND but because we were satisfactorily armed. The Soviet Union looked across the water, saw that we and the United States were armed, and chose not to do what it might otherwise have done. Had Margaret Thatcher not stood firm on the subject of cruise missiles outside Newbury, for example, I am clear that the Soviet Union would still be in existence today, and there is at least a risk that some parts of western Europe would be dominated by that evil empire.

I am not one of those who would do away with arms because they do not like them. Our arms are a necessary part of preserving peace. After all, no one says to an armed policeman, "If you put your baton down, Britain will be a safer place." Sadly, outside this Palace today we see policemen who are armed because it is believed that bad guys are trying to get into this place with guns. Asking a policeman to put his guns down would not mean that the bad guys would do likewise. I was struck by that aspect of one or two contributions this afternoon. For example, Clare Short indicated that if others did not have such weapons, we should not have them either. That argument is quite wrong. It seems obvious to me that we are the good guys and that they are not; it is therefore perfectly reasonable that we should have such weapons.

In my opinion, arms are the balance of peace. Indeed, the motto of my regiment, the Honourable Artillery Company, is "Arma Pacis Fulcra". One must have arms to achieve peace. Does any Member present who speaks with honesty and sincerity seriously believe that if we were to snap our fingers and say "We are no longer a nuclear force"—if we were to say "Follow us, O world, for we have done the right thing: we are doing away with Trident and not renewing it"—the world would be a safer place?

Incidentally, those who support the "delay" amendment, notably the Liberal Democrats, are merely fooling themselves, or fooling the people out there. This evening we must reach a decision: either we support the notion of nuclear deterrence, or we do not. While I respect the argument of those who say that we do not, it is not my argument.

I do not believe that even those who have spoken from the CND standpoint believe that the world would be a safer place if we abolished nuclear weapons. We all know perfectly well that if we did away with them, or indeed with conventional weapons—for the same argument applies to them—the world would be a worse place, not a better place.

It is with a heavy heart, in a sense—because I personally feel unhappy about these matters—that I concluded that I would support the Government this evening.

It is always difficult to participate in debates in which the traditional sides do not necessarily line up, and one finds oneself alongside dear friends and colleagues who take a different view. It is somewhat uncomfortable. I can tell the House, however, that I will support the Government this evening—I have not changed my views on these matters for many years—and also that it is not nearly as uncomfortable tonight as it was in 1982-83, when we debated the defence of the country in the context of the arguments and battles taking place in the Labour party at the time.

One of the allegations made about today's debate is that it is premature, and that we should not be here because the widespread debate that the country would expect us to have about this important issue has not taken place. That has not been my experience over the past six months—I have been inundated with representations from all kinds of people with a legitimate interest in the issue—and, indeed, the original decision to reach a conclusion at about this time was made some years ago. I think that there has been a wide debate, and that that has been reflected in the speeches today. Many different views have been expressed, some of them very unexpected, by Members in various parts of the Chamber.

Like others, I do not intend to hog the debate, but I want to make a couple of points based on the representations that I have received. One of the key points made to me has been that if the United Kingdom renews its Trident submarine, it will breach the non-proliferation treaty. I do not accept that that is the case, and I think the public should be told loudly that it is not the case.

The non-proliferation treaty was drawn up as a deal. As it has already been mentioned by other Members, I will not go into what the deal involved, but the treaty was drawn up prior to 1967 by the countries that were then nuclear powers, with the aim of reducing their nuclear capacity over a period in return for concessions on civil power and so forth. It was not about unilateral disarmament. Does anyone in the House think that the Russians, the Americans or the Chinese would have signed a non-proliferation treaty if they had thought that they were signing themselves up to unilateral disarmament, and would not be able to renew the weaponry that they had?

There is a very fine line between maintenance and renewal. We have already seen that in China, and investment in new nuclear weaponry technology is currently taking place in Russia. If Mr. Gorbachev has lessons to teach the British, he also has lessons to teach the Russians. The song he is singing now is not the song he was singing when I met him in Moscow many years ago. The nuclear non-proliferation treaty is about trying to de-escalate nuclear dependency. It is in that context that the world's courts must interpret it. We must strongly say that.

Another representation that has frequently been made to me—it is an argument that was made by Clare Short—is that if Britain renews its nuclear capacity, that will send the wrong message to other countries who want to rearm. It might send the wrong message, but it will not change the decision that such countries will make or try to make, because fascists and totalitarian people and dictators do not listen to the logic of the kind of debates that we have in this House. Instead, they ask, "Can we throw our weight about more if we have a nuclear weapon?" and they say, "If it is possible for us to get a nuclear weapon, we will try our best to get that weapon." To repeat a point that was made by the Conservative Front-Bench spokesman, if another country does not have that weapon, such people will be the first to say, "No, we will not engage in a diplomatic argument about the issues before us, and we will not even have a conventional warfare argument about our problems"—whatever they might be about, such as oil, Russia or the middle east—"because we have nuclear capacity and we know that you don't have nuclear capacity and that is all that matters." I could talk a lot more about that.

Representations have also been made to me that we do not know, and cannot imagine, who the enemy is. My hon. Friend Joan Ruddock made that point. However, that is the main reason for having a deterrent. According to the doctrine of uncertainty and ambiguity, we must invest in the cutting-edge of defence technology in the hope that others will understand that we are doing so and we will never have to use what we develop. If we do not invest in that, we will leave ourselves wide open to attack—or blackmail, which can be even worse—by others who hold different views from us.

I am currently reading a book for fourth level students about the history of Britain, and it is interesting to learn what people at one point in time thought would happen in the future and what actually happened four or five years later—in Scotland among other places, I might add. It is hard to predict the future. We do not know what will happen in China. What will happen if China breaks up into different parts? What will happen if Russia breaks up into different parts, or if someone who makes Putin look benign takes over and decides to throw their weight around within the Russian sphere of influence or in the middle east? If we have given away our nuclear capacity and we then try to have diplomatic or other arguments with such people, we will be in a very weak position. We do not know what the future holds.

My views on this matter are not in any way connected to always supporting the Americans. I do not always support them; I did not do so on Iraq. However, that is, in a sense, a short-term problem. The decision that we are discussing is a much longer term decision. I believe that we must take it in principle. It is no use saying that we will wait until 2014, which is what the Liberal Democrats are saying. It has been conceded this evening that the Liberal Democrats have no argument against the principle of nuclear capacity, and I am glad that they are prepared to support the design and development of any new capacity. However, I say, not only to Liberal Democrat Members but to some of my party colleagues, that that is not enough. What we are discussing is a big decision. We have to tell the British people what we believe in—what our principles are.

Several hon. Members:

rose—

Order. Many hon. Members are still seeking to catch my eye. I have therefore decided to invoke the shorter speech rule, which will operate from approximately 5.42 pm. From then, speeches will be no more than four minutes long. I hope that that will enable more Members to speak in the debate.

Like a previous speaker, I have received not a single letter from any of my constituents urging me to vote with the Government tonight in favour of replacing Trident. However, not for one moment do I think that there is not a strong understanding in my constituency and throughout the country of the need for this House to vote in favour of a replacement tonight. Yes, our constituents put us here to talk about the most immediate and pressing issues that they face, and for many those are public services, NHS dentistry, and the closure of accident and emergency wards and local tax offices, for example. However, they also put us here to take the difficult and unattractive decisions that do not satisfy any immediate interests, but which are nevertheless vital to the national interest. The decision before us tonight is one such decision.

A number of constituents and local church and environmental groups have contacted me, expressing concern about, and opposition to, the notion that we should support replacing Trident. I do not intend to discuss all the various arguments, a number of which have already been covered more than adequately, but one idea that has some currency in the country is that Parliament has not been given enough opportunities to examine rigorously all the issues affecting the decision that we are about to take. That notion has been scotched well and truly, however. There have been three Select Committee reports and a White Paper, and numerous opportunities for Members to visit Her Majesty's naval base Clyde, at Faslane and Coulport, in order to have frank discussions with a wide variety of service and civilian personnel in management and operational roles, and to question them about the nature of our deterrent and how it is managed. So Parliament has had adequate opportunity to scrutinise the issues before us.

A number of my constituents have also expressed the view that since the end of the cold war, the world has changed so fundamentally that nuclear weapons and the nuclear deterrent are redundant. A local church group said to me that since 9/11, the world had changed so much that nuclear weapons had no place any more. It is true that since the end of the cold war, the nature of the threat has changed; no one is pretending otherwise. It is also true that our nuclear capability and posture and the configuration of our nuclear resources have changed to reflect that change.

In some of the correspondence that I have received, the view has also been expressed that since 9/11 a new era has been ushered in, in which terrorist attacks have displaced the threat of strategic nuclear strikes, and that because nuclear weapons are less relevant in the war on terrorism, they are redundant in this new era. That view is dangerously misguided. Of course nuclear weapons are futile in deterring someone from blowing themselves up on the No. 12 bus, but so is most of the kit that comprises most of our conventional warfare capability. The fact is that the nuclear deterrent serves a very limited but vital purpose: to help create the conditions in which a nuclear attack on the United Kingdom would be futile, and therefore highly unlikely.

There has been a lot of discussion this afternoon of what is unknown about the future strategic threats that this country will face in the decades ahead. There is indeed a lot that we do not know, but there are some assumptions that we can make. We can assume that the number of countries seeking to acquire a nuclear capability will increase. Although we might have no idea of the intent in the decades ahead of countries that will have such a capability, we can fairly safely assume that the march of political freedom and liberalism across the globe will not progress uniformly. There will continue to be points of collision between the values of liberalism—it is one of our country's destinies to promote those values throughout the globe—and manifestations of tyranny. So it is not totally outlandish to envisage a scenario in which the UK might once again be a target of a nuclear state.

In a world in which an increasing number of rogue states and illiberal regimes are seeking to acquire a nuclear capability, it is essential that a core of strong liberal democratic nations retain their nuclear deterrents for the foreseeable future. While it is difficult to identify any nation on earth now whose nuclear capability combines with an aggressive intent to pose an existing threat to the UK, the fact is that we can never say that such a threat will not re-emerge in the decades ahead. A minimum credible nuclear deterrent is therefore vital. Trident has proved successful as a flexible and secure platform for maintaining that deterrent, and the time has come for the House to make the positive decision to replace it.

Unlike the Foreign Secretary, I was never a member of the Campaign for Nuclear Disarmament. Nor have I ever been a unilateralist or a pacifist. On the other hand, I have never had anything to do with the kind of swivel-eyed, Dr. Strangelove-type reactionaries, who for some reason I always associate in my own mind with Dr. Lewis.

There is something worrying about the occupants of the two Front Benches coming together on an issue that has echoes of Iraq all over again. Much of the argument has been made on the basis of fear, uncertainty and disinformation. We all know where similar arguments took us in March 2003. This is obviously a different subject, and there are strongly held feelings on both sides. I also appreciate that some hon. Members have strong constituency interests, but I have noted two points especially in the debate today.

The first was a point made by my hon. Friend John McDonnell when he said that he had a sense of déjà vu. So did I, especially when I heard the speeches by my right hon. Friend Sir Gerald Kaufman and Sir Malcolm Rifkind. They had the benefit of consistency in what they had to say, but they were talking about a situation that obtained 20 or 25 years ago. Matters have moved on a great deal since then.

The second point is about the way in which the same tactics are employed to knock down propositions that have not been put. I have heard many references to unilateral disarmament, as if hon. Members would have a chance to support that option tonight. That is not true; it is a fallacious argument, and it is typical of the kind of debating cul-de-sac that we are taken into on such occasions.

The key question is time. I am reminded of the classic film "Clockwise". The John Cleese character organises his day to the very second so that he can ascend to the heady position of chairman of the Headmasters Conference. Of course everything goes awry, but he is determined to have his day. I tend to think that this debate is connected to the Prime Minister's approaching abdication from his post. That is behind the rush to push the issue to a conclusion tonight. I can see no other reason why this decision must be made now.

Many hon. Members have talked of this decision being an insurance policy. This must be the only insurance policy to be taken out against we know not whom, based in countries we know not where, and with weapons we know not what. We are told that at some point in the indeterminate future we may need weapons against a country that will repeat the threats of the 1970s and 1980s. Frankly, I just do not buy that.

Nor do I buy into any of the other arguments that have been put about the need to take this decision now. I wonder why the Americans need a mere 13-year lead-in time to build one of their superior submarines, compared with the 17 years that we need. That is very odd. We will also be going back to the very same supplier who provided us with an inferior product before, which—according to the latest Government estimates—will last only 25 years, when the Americans' system lasts 40 years. That is most perplexing. What happens to our procurement policies—

Let me deal with the point about the design life of the submarines. They were ordered to last for that long. They were designed for 25 years because that is what the Government of the day said that they could afford to buy—not because the people who built them could not make them last longer. They could, of course, have made them to last longer, as the Ohio class submarines were, but they would have cost much more.

I am grateful for the Secretary of State's advice, but that was 30 years ago, and time has moved on—not only that, but it depends on who we believe about the design life of these particular vessels. Until comparatively recently, we were told that the lifespan of the Vanguard class submarine was 30 years minimum—not 30 years maximum, not 25 years with a possible extension of another five years, but 30 years minimum. [Interruption.] It is all very well for Opposition Members to point to the Select Committee report, but I am telling the House what Ministers and senior members of the Ministry of Defence—including Lord Moonie, with whom I checked this information today—stated at the time, as a matter of public record. They were adamant that there would be a minimum life of 30 years.

Is it not strange that our American friends base the life of their vessels from the ship-going period of their commission rather than from when they are first launched, as there is a gap? If the figures are fiddled around with, it is possible to argue, given the lead-in time and the lifespan that we now attribute to those vessels, that we should be putting in our orders now. It seems, however, that the figures—and, indeed, part of the science—have been conjectured to fit around the political desirability of taking a decision now.

We are told that we have expert advice. The one issue on which I agreed with the Prime Minister on 4 December was the fact that such things are "a matter of judgment". It is indeed a matter of judgment, and for every scientist who says that this is what we should be doing now, other scientists can be produced who say the opposite. For example, Dick Garwin has already been mentioned, and advocates of the Select Committee's paper will agree that he appeared before it. However, Dick Garwin did not speak, as someone claimed he did, only on behalf of Philip Coyle; he also spoke on behalf of Ted Postol, who designed the Trident system in the first place, and Frank von Hippel, who was one of the designers of the warheads that we copy.

I have to say that if eminent scientists are giving advice—they actually believe in nuclear deterrence and are party to these decisions not only as scientists, but as leading members of various administrations—it behoves us to listen to what they have to say. We should not be bounced into taking a decision here tonight that pre-empts the sort of informed debate that needs to happen before the House can take a properly objective and science-based decision.

In the current uncertain international situation and all the threats of proliferation, I believe that this is no time for Britain to give up its nuclear deterrent. North Korea has already tested a nuclear weapon and Iran is in the process of developing nuclear weapons. Those developments clearly put pressure on other powers in their regions to consider acquiring nuclear weapons themselves. Such proliferation could lead in the longer term to a possibility of one or more such states posing a threat to Britain.

The goal that we should all be striving for is to rid the world of all its nuclear weapons, but I do not believe that that can be achieved by Britain unilaterally giving up its nuclear weapons. We must participate in multilateral negotiations. In that context, the next nuclear non-proliferation treaty talks in 2010 are of immense importance, and the Government should be doing all they can to make those talks a success.

What I find puzzling is the Government's proposal to declare now that we will proceed to build replacement Trident submarines after the conclusion of those talks, irrespective of their outcome. That is a proposal whose logic I simply cannot understand. In order to maintain Britain's nuclear deterrent, the only decisions that need to be taken now are to participate in the missile life extension programme and to commence the initial concept and design work for the replacements to our Vanguard-class submarines. I believe that the Government should authorise that work. However, I do not support the Government's decision now, which is far too premature, to build a new generation of submarines some time in the middle of the next decade.

Does the hon. Gentleman therefore agree with what I understand is the Lib Dems' policy—cutting half the Trident weapons and extending the life of the other half for seven years?

I certainly support Liberal Democrat policy, and I will come to that later in my speech.

If we had to take the decision today to build replacement submarines I would certainly vote in favour, but we do not need to take the decision for several years. The Government should have asked Parliament today only to authorise participation in the missile life extension programme and to start the concept and design work on possible replacement submarines. It is vital that Parliament should be given a future opportunity to vote on whether we actually proceed to building the replacement submarines.

I simply do not understand why the Government want us to take that decision today. I can only speculate that the Prime Minister wants to take as many decisions as he can before he leaves office. He seems to want to commit the Government to decisions that do not need to be taken until after he has long gone.

The vast majority of the costs associated with any replacement system would begin to be incurred only at the main-gate approval stage. That is when the actual manufacture of replacement submarines would begin. The concept and design work that takes place before main-gate approval incurs only a small proportion of the overall procurement costs. Therefore the final decision on whether, and if so how, to procure any successor system could be taken at any point up to a decision on main-gate approval without incurring significant procurement costs. The main-gate approval for the replacement submarines is likely to take place in about 2014.

Scheduling the final decision for a more realistic date in the next decade would give Britain several years that should be put to good use in trying to create the circumstances in which maintaining our nuclear deterrent would prove unnecessary. As I said in response to the intervention, I fully support the Liberal Democrat proposal of an immediate cut in Britain's nuclear arsenal of 50 per cent. to reinvigorate multilateral disarmament talks and re-energise the negotiations. The remaining warheads would be sufficient to provide Britain with a credible deterrent.

Can the hon. Gentleman explain exactly which 50 per cent. he would cut?

Fifty per cent. of the current missiles would be cut. Such a significant reduction to Britain's nuclear arsenal would send a strong signal that Britain continues to meet its obligations under the non-proliferation treaty and is serious about cutting nuclear weapons. If Britain used all its influence to spearhead a renewed drive towards disarmament and expressed a sincere willingness to give up our remaining nuclear weapons if sufficient progress were made towards total worldwide nuclear disarmament—in partnership, I hope, with a more sympathetic American Administration after George Bush has gone—the next NPT review conference in 2010 could make progress again after the failure in 2005.

By keeping our options open for some years, we can make a final assessment of whether we need to insure against an uncertain future with the advantage of being several years closer to that future and better able to judge it. Taking a decision on replacing the Trident submarines now pre-empts the outcome of the 2010 talks and greatly reduces the chances of their success. We should do all we can to make the talks a success and, after the talks, review the situation. If sufficient progress has been made by then towards a world free of nuclear weapons, we may not need to build replacement submarines. On the other hand, the talks could fail, in which case the right decision will be to build replacement submarines to carry the Trident missiles. But that is a decision to be taken in the middle of the next decade, not now. The Government have failed to convince me in the debate of the need to take the decision now, so I shall be voting for the amendment to postpone the decision to build replacement submarines.

Several hon. Members:

rose—

Order. The four-minute limit on speeches now operates.

When my hon. Friend Jon Trickett spoke earlier, he outlined the consequences of using nuclear weapons. They have been used only once in aggressive wartime—in Hiroshima and Nagasaki in Japan in 1945. Last month, we had a large demonstration in Trafalgar square against the replacement of Trident nuclear missiles. We had a video link-up with the mayor of Hiroshima, who pleaded with us to do everything that we could not to develop a new generation of nuclear missiles in this country, because people in his city were still dying as a consequence of the weapons that were used more than 60 years ago. That is the consequence of nuclear weapons.

This morning, I had an e-mail from the mayor of Salt Lake City, speaking on behalf of the Western Shoshone tribe. He pointed out that in the past Britain and the United States have undertaken tests in Utah, which have resulted in a large increase in cancers, thyroid cancers and all the health problems that go with them. Developing nuclear weapons—never mind using them—involves consequences for people's health.

I remind the House that a few years ago we debated with great earnestness the situation in Iraq in relation to weapons of mass destruction. A nuclear weapon is automatically a weapon of mass destruction. It cannot be targeted individually at a military target. It can be used only to destroy a whole area and to kill a very large number of people. It has no deterrent effect whatsoever. We are promoting this position largely through a sense of vanity, rather than anything else. If we pass the resolution tonight to endorse the Government's position, we will be set on a road that is both costly and illegal.

I want to make two points about the law relating to this issue. There is something called international humanitarian law and there are two important principles that are part of it. First, there is the general rule that a party to an armed conflict must always seek to distinguish between the civilian population and the combatants. A weapon that is incapable of drawing such a distinction is unlawful under international humanitarian law. A nuclear weapon cannot, by its very nature, make that distinction. Secondly, there is the principle that a party is entitled to use only that force that is required to achieve a legitimate military objective. A weapon that is bound uselessly to aggravate the suffering of combatants is unlawful under international humanitarian law.

When the Foreign Secretary spoke earlier, she took great pains to tell us that we were adhering to the principles of the non-proliferation treaty. I would argue strongly that we are not. The whole point behind the treaty is to stop the proliferation of weapons. If we develop a new generation of nuclear weapons, what moral authority do we have to say to any other country in the world that they cannot develop a generation of nuclear weapons? I ask the House to think who has greater moral authority around the world: the spokesperson for the British Government or Nelson Mandela on behalf of the people of South Africa, which unilaterally gave up its nuclear weapons and any pretence thereto?

I would also make the point that in 1996, the International Court of Justice ruled that

"the threat or use of nuclear weapons would be generally contrary to the rules of international law applicable to armed conflict and in particular the principles and rules of humanitarian law."

We face an important decision tonight. Either we endorse this vast expenditure, or we encourage a public debate that I believe will come down on the side of sanity, sense and peace in the world, and we do not go ahead with this vast expenditure that can lead only to a more dangerous world.

I will be brief. [ Interruption. ] I will have to be brief. That is four seconds gone.

There is considerable misunderstanding in the House about what we are deciding. The Foreign Secretary's comments that we are not committing ourselves irreversibly to a nuclear deterrent, but are taking steps to maintain a nuclear deterrent beyond the life of the existing system, are important. When the Secretary of State for Defence sums up, he cannot emphasise that strongly enough. I had the privilege of visiting HMS Clyde last year as part of the armed forces parliamentary scheme. No one who visits there could fail to be outstandingly impressed by the professionalism of our armed forces. That professionalism equips members of the Royal Navy not only to spend 90 days at the bottom of the sea—not something that I would relish—but to deliver the extraordinarily impressive security arrangements that I saw. My visit clarified some of my thoughts about whether we continue to need a nuclear deterrent.

There is clearly much on which hon. Members agree. Although this sounds like motherhood and apple pie, it is important to make the point that none of us wants to have a nuclear deterrent. We would all wish that the resolution of conflicts throughout the world could be brought about by negotiation. However, we live in the real world, and the real world has become less safe. I was not a Member of the House when the decision on the invasion of Iraq was taken. I regret that decision deeply, and I believe that its repercussions will be with us for many years to come. However, none of us can predict with any certainty the threats that this country will face over the next 20 years.

There are three points that I would like the Secretary of State for Defence to clarify in simple terms that can be understood by hon. Members, especially those who have concerns about the proposal. We need a justification for why the decision needs to be taken now. I have something in common with Emily Thornberry, in that I am utterly confused by the Liberal Democrats' position.

We need to know whether the replacement of any part of the deterrent will remain solely and completely in the control of the UK. We also need to know whether the process would harm or compromise any part of the non-proliferation treaty. Will we continue to pursue a reduction in nuclear weapons and will multilateral disarmament continue to be our aim?

My right hon. Friend Mr. Arbuthnot probably summed up my view almost word for word: with some unhappiness, it is yes to the decision tonight. However, I was especially struck by a point that he raised about dependence on the US. If we do not want to be entirely dependent on the US, we need our own nuclear deterrent under our own control.

We have had a thoughtful and interesting debate. This is one of those times when I wish that the public were watching. We have heard heartfelt contributions on a subject that is at the centre of what we are all here for—the security of the United Kingdom and its citizens.

Twelve months ago, when the Defence Committee started its first inquiry on Trident, I adopted a fairly sceptical approach. However, several issues have become clearer to me over those 12 months, principally the question of the timing of the decision. Believe me, if I thought that it was reasonable to delay the decision until after the next election, I would be voting for that tonight and I would have been urging the Select Committee to make that one of its recommendations. However, we must consider the industrial base and skills that are required. All the advice that we received from the UK military said that the process would take 17 years. Our first report questioned why the time period was 17 years rather than 14 years, which was the case at the time of the 1980 decision. We have heard a good explanation for that—although the initial design and conceptual work had been done prior to 1980, it has not yet been done at this stage.

I am surprised by the attitude of the Lib Dems. They have made it clear that they support that design and conceptual work. If they felt that they were being bounced into making a long-term decision to commit themselves to four boats between 2012 and 2014, they had the opportunity to table an amendment providing simply that they would agree to the initial design and conceptual work. I have read the amendment that most Lib Dem Members have signed, but such a provision is not in there. It seems that a lot of people are playing the "I'm a multilateralist, but I want to avoid making a decision" card.

I remember knocking on doors in the 1980s when the Labour party had a unilateralist position. I was comfortable with that, but it seemed to me that while some people were passionately in favour of that position—they would put up posters and deliver leaflets, and they wanted a Labour Government who would get rid of nuclear weapons unilaterally—many lifelong traditional Labour voters shuffled away, would not look one in the eye and ended up voting for the Social Democratic party, which was largely made up of ex-Labour people who had joined because they did not feel happy with our unilateral position, and then for the Liberals.

In 1989, Labour changed its decision at its party conference, and many of us found that difficult. However, I have fought four general elections, and won three of them, on party manifestos that promised to retain Trident and to take a multilateral approach. The Labour party's approach is that we will get rid of nuclear weapons only through negotiations, in which we say that we will put our nuclear weapons in the pot if other nuclear states do the same. That is the policy on which all three major parties fought the 2005 election.

It would be undemocratic if we made a decision today that made it impossible for the people of this country to elect, in three years' time, a Government who could build a new Trident successor. If the White Paper had put forward the view that we should not replace Trident, I would have expected an honourable Government such as ours to recommend that the design work and work on the initial concept still went ahead, so that if, in three years' time, a Government were elected who wanted to retain the nuclear deterrent, they would have the capacity to do so. If we do anything other than back the Government motion tonight, we will go against the manifesto commitment that more than 600 Members—

Order.

It would be easy to convince ourselves in this debate that the world would be better off without nuclear weapons—we could all agree with that. We could also easily convince ourselves that we could do something more productive with £15 billion or £20 billion, but neither of those points are the issue. We have a responsibility not to decide the issue in a way that makes us feel better, but to make the decision that we think is best. I accept that that is difficult, because we are trying to develop a response to the security threats of the next 20, 30, 40 or even 50 years, which we cannot foresee. The point has been made that it is impossible to predict the world of the 2050s.

Hon. Members who spoke against the motion said that the most important threat that we face is not a nuclear power; it is climate change or world terrorism. I am sure that they are right, but who, 30 or 40 years ago, would have predicted that those would be the primary threats? The answer is very few people indeed. We have to project forwards, and ask whether we hon. Members are making similarly inaccurate predictions. Our judgments are based on educated guesswork. In some cases, it is highly educated guesswork, but it is guesswork none the less. In those circumstances, I prefer to err on the side of caution. If we do not know what threats we face, surely we must do our utmost to be ready for everything.

Even if the threats of today are those that we will face in the next 30 or 40 years, it is hard to argue that we face an increasingly safe world. It is quite the reverse. Some nations, which have already been mentioned, are developing nuclear capacity, so it is a spectacularly inappropriate time for Britain to be abandoning its nuclear deterrent. I do not accept the argument that that is not what we are discussing today; it is exactly what we are discussing. If we defer the decision, we may find that it is taken out of our hands. We cannot choose between keeping the deterrent and updating the deterrent; it is one and the same thing, because a deterrent that is out of date is no deterrent at all.

I shall briefly deal with the main arguments against the motion. The first is that we set a bad example by renewing Trident and that we weaken our hand as regards non-proliferation. I do not accept that, and I do not believe that we are in breach of our non-proliferation obligations by renewing what we already have; that is not proliferation. I do not accept that we weaken the message that we send, or that we send the wrong message. The wrong message to send would be a refusal to renew Trident. At this moment in history, that would send precisely the wrong message—a message of weakness when we need to project strength. It would also be a message of complete irrelevance, because I do not believe for a second that if our country gave up what amounts to 1 per cent. of the world's stockpile of nuclear weapons, it would affect anyone's judgment in any way.

Secondly, I do not accept that the decision is precipitate; this is the right time to make it. We should err on the side of caution. If we do not take the decision today, we could find that our manufacturing and expertise capacity has been diminished to the point where we cannot make another decision when we want to do so.

I shall vote cautiously. I will not take chances with our national security, nor will I play political games with it. I shall vote for the Government's motion.

Had I been asked to deliver this speech 35 years ago when I was a young, idealistic student, I would have taken a different view and given a different speech. There are a number of reasons why I have changed my position. My support for the new programme is not based simply on its economic benefits for the south-west defence-based industries, although understanding the complexity of the procurement process and the nature of their highly skilled work has informed my position.

As we have heard in powerful speeches from colleagues in all parties, there are a number of key issues and questions. Do we need the deterrent? What is the threat now that the cold war is over? Are there legal arguments against the ongoing programme? They are good questions. Many colleagues pressed the point about where the future threat lies. Is there a threat? I do not know, but we cannot take risks. None of us is psychic. We do not know what the threat will be in 20, 25 or 50 years' time. We cannot work on the assumption that we will be able to get by on our stock of conventional weapons if a threat emerges at some future date. Leaving until later a decision on the go-ahead for submarines capable of launching the missiles—the decision is about giving the go-ahead for the submarine procurement process—could leave the UK facing an enemy with one arm tied behind its back.

We cannot rely on diplomacy to get us out of any future confrontation. It would not be rational to do so. Relatively recent history shows that such an option could leave our nation exposed. In the 1920s, following the war to end all wars, disarmament was the preferred option, for reasons we all understand. However, military dictators stepped in to fill the vacuum, as my right hon. Friend Mr. Raynsford described earlier, because certain western democracies were seen as vulnerable. Diplomacy failed us then, and we were not prepared. It took the Herculean efforts of armament workers in the UK who rushed to produce weapons, as well as the incredible bravery of our service personnel against enormous odds, particularly in the early years of the war, to get us to the point where victory was possible.

Delaying the decision would be disastrous on defence grounds. Abandoning the programme may be a desirable outcome for many colleagues in this place and could be welcome in other quarters—probably foreign Governments who have no nuclear weapons and no desire to build them. However, there is no evidence to suggest that such a course of action would encourage others to follow our lead. I can see no way in which it would give states developing nuclear weapons—North Korea, Iran, Pakistan, India or Israel—any reason to stop their programmes. Indeed, it could have the opposite effect.

In Plymouth, a city associated with the armed forces and one of the cities most heavily bombed during world war two, we understand the deterrence process. Equally, we understand the importance of the SSBN—ship submersible ballistic nuclear—programme to the economy of our city and the wider south-west, as well as to the UK's maritime industrial base. My colleague, my hon. Friend Linda Gilroy, has already made that case well. I can but reiterate the point that the importance of a decision to continue with Trident—on what is generally seen throughout the House as the most effective delivery platform for the missiles—cannot be overstated.

What we have in Plymouth is unique and what the defence industry requires is also unique. Admittedly, our skills could be used in other fields, but only the Ministry of Defence buys submarines and wants maintenance programmes for them. In Plymouth, we have the skills. Submarines cannot be conjured out of thin air if the strategic position changes at a future date. They cannot be built in the same way as fighter planes were rushed out in the second world war.

No one can feel comfortable in a world where nuclear weapons exist, but we do not live in a secure world environment. Twenty years down the line, I certainly do not want to have to explain to a population threatened by a state with nuclear weapons that we do not have the capability to respond.

The question before the House is very simple. We are being asked whether we want the Government to proceed with the preparation of the continuation of our nuclear deterrent in some years' time or not. Any amendment or rejection of the motion will mean that the House has instructed the Government not to continue with the concept, work on and preparation of the submarines.

A lot of this debate has turned on the question of the timing and the Select Committee, of which I am a member, looked at the issue carefully. Professor Garwood has been mentioned, among others, as someone advocating the idea that we had space for delay. The Committee considered this and other evidence and not a single member was convinced.

The misunderstanding arises from the different ways in which the two respective powers—Britain and the US—use the submarines. We simply have four submarines; at any time, we have one at sea, one in refit, one going to operations and one spare. That is the way in which we operate. The Americans have a very large number of submarines. We took evidence from Rear Admiral Andrew Mathews, who is director general, nuclear. He made it perfectly clear that we operate in a different way. The lifetime of the submarines is shortened because we use them more intensively and rely upon using them more intensively. To get, as he put it, one from four is much more difficult than two or three from 14, which is what the Americans do.

Moreover, we can extend the life of the submarines to 25 or 30 years, but their reliability declines over the period. Because the Americans have that spare capacity in their much greater build, they can afford that redundancy and unreliability. We cannot, if we are to maintain our deterrent. That is why the decision needs to be taken today.

My only other comment is about the strategic context. Nick Harvey said that the world was watching us today. The one way of making sure that the world will watch us no longer and give us no influence is to wantonly throw away the influence we have. By wantonly throwing away possession of our nuclear weapons, we will give something for nothing. I commend the speech of Mr. Henderson who dealt with the proliferation point extremely well. If we throw away our weapons, the world will watch us no more and will take no interest in anything that our Government have to say.

I am very proud of the Labour Government. My constituency has record employment; we have seen the introduction of the minimum wage; there is justice for pensioners; there is record investment in our public services. I hope that Front-Bench Members recognise that when someone like me votes against the Government and resigns as a parliamentary private secretary at the Department for Health, it is not an easy decision. It has been a hard decision, but I believed that I should come to the House to explain it.

As the House is aware, Robin Cook was my predecessor. The week before he died in August 2005, the very last article he wrote was in The Guardian on this subject. He said:

"It was the Wilson government of the 60s that built, launched and named the Polaris fleet. It was Jim Callaghan who first struck the Trident deal with President Carter... There could not be a more convincing way for Tony Blair to break from the past and to demonstrate that he is a true moderniser than by making the case that nuclear weapons now have no relevance to Britain's defences in the modern world... the spirit of the cold war lives on in the minds of those who cannot let go of fear and who need an enemy to buttress their own identity. Hence the vacuum left by the cold war has been filled by George Bush's global war on terror...nuclear weapons are hopelessly irrelevant to that terrorist threat. The elegant theories of deterrence all appear beside the point in the face of a suicide bomber who actively courts martyrdom. And if we ever were deluded enough to wreak our revenge by unleashing a latter-day Hiroshima on a Muslim city, we would incite fanatical terrorism against ourselves for a generation."

I hope that when my right hon. Friend the Secretary of State for Defence sums up, he gives some indication of when he would see a nuclear weapon being used.

The article pointed out that

"all levels of the Trident system depend on US cooperation. The missiles are not even owned by us, but are leased from the Pentagon in an arrangement that Denis Healey once dubbed as 'rent-a-rocket'. Renewing our collaboration with the US on nuclear weapons will deepen the bonds between Downing Street and the White House, at the very time when the rest of the nation longs for a more independent stance."

It is absurd that Britain should maintain its nuclear weapons to guarantee its security while lecturing Iran, et al, that the safety of the world will be compromised if they behave in the same way. Despite the anxieties about proliferation, more nations have given up nuclear weapons in the last generation than have developed them. It has been pointed out that Brazil, Argentina, Ukraine and South Africa have given up weapons, and none of them regard themselves as less safe or secure than before; nor need we if the leadership can find the courage to allow Trident to be the end of Britain's futile and costly obsession with nuclear weapon status.

In an aside to Conservative Members a few moments ago, Mr. Salmond asked what it would be like to have a facility like Faslane in the Thames valley. If he came and stood in my bedroom —[ Interruption ]—a remote possibility, I grant, and looked across the Kennet valley, which is part of the Thames valley, he would see the rooftops and chimneys of the atomic weapons establishment at Aldermaston, which I revere for the work that it has done to safeguard this country's security in times past and, I hope, in times future.

I am sure that the hon. Gentleman will understand when I say that I wish that that facility did not exist. More precisely, I wish that we lived in a world in which the atomic weapons establishment at Aldermaston did not need to exist. Unfortunately, however, we live in the real world, not in a utopian one. If the hon. Gentleman came with me to the hill above my house, and looked further into the distance, he would see Greenham common, which is a living, breathing example of the peace dividend. More people work there in real jobs than were stationed there at the height of the cold war. The arguments around the perimeter of Greenham common now are about planning issues and whether the missile silo should house a museum or be used as a storage site for cars. That achievement demonstrates previous Governments' strength of purpose and the support and the sacrifice on the part of Members on both sides of the House.

In the short time available, I should like to address the points made by Nick Harvey about the timing of the decision. He suggested that it was a political decision, rather than a strategic one. He suggested that in the dog days of his premiership, the Prime Minister, from hitherto unnoticed altruism towards the Chancellor, should make a decision that was causing agony in his own party. I have more generosity of spirit than the hon. Gentleman, as I believe that the Prime Minister and the Government have made the decision now because it is the right decision to make. I refer many hon. Members who have made speeches today to the Defence Committee report, as it is apparent that they have not read it. It is crucial for anyone who is considering adopting the position proposed by the Liberal Democrats to understand the way in which the Defence Committee came to accept that extending the life of the submarines was not sufficient and that we could not make a decision any later. I accept that, originally, the documentation suggested that it would be possible to make a decision in 2010. It is now accepted, however, that initial conceptual work must be done on those submarines before the 14-year period to which the hon. Member for North Devon referred, making a total of 17 years. When one compares the evidence of Professor Garwin, supported by the Oxford Research Group, with that of organisations such as the Royal United Services Institute and, more importantly, the Royal Navy, the evidence comes down firmly on the Government's side of the argument.

I support the retention of Britain's nuclear deterrent. I also support the renewal of Britain's nuclear deterrent. I am sorry that the amendment tabled by my right hon. Friend Mr. Denham, my hon. Friend Fiona Mactaggart and me was not selected. The choice before us today is to take no decision at all or to take an irrevocable decision to continue with Trident as our platform for nuclear deterrence over the next 40 years.

If we support nuclear deterrence and renewal, we clearly need to look at the future of that deterrent, so we need to take decisions about how we approach the concept and design of a replacement nuclear deterrent. However, we live in a rapidly changing world. That was reflected in the strategic defence review, which stated that the strategic environment that we face today is very different from that of the previous 50 years. The review concluded:

"The challenge now is to move from stability based on fear to stability based on the active management of these risks, seeking to prevent conflicts rather than suppress them."

What might that doctrine look like in the context of future nuclear policy? That was articulated well by a witness to the Defence Committee, Dr. Stocker, who said:

"In today's so-called 'second nuclear age' where national survival is probably not at stake, threatening to devastate another society in total or in large part is neither appropriate nor credible, so actually deterrent credibility may now be based on our ability to threaten the least amount of damage to another society, but in a scenario in which nuclear weapons are relevant because somebody else is threatening to use nuclear weapons or other WMD".

According to that doctrine, is Trident the right replacement for Trident over the next 40 years? Does a system which was designed as part of a mutually assured destruction system fit that description of possible future deterrence? Is it wise to go ahead irrevocably with that system, without considering alternatives? It appears that there are alternatives, which should be considered in the process of renewal and in the context of concept and design, so that when we come to take a decision at gate entry, we have the concept and design most appropriate not for a cold war scenario, but for a continually changing world.

As things stand, we may have a Trident system that lasts until a few years away from the time when we claim that we will have reduced our carbon emissions by 60 per cent. from 1990 levels and will be living in a different world and a different economy. We need to take decisions on design and concept, and on the future, but I am not convinced by the argument that we should commit ourselves irrevocably today. I do not believe that future investment hangs on this decision. I do believe, however, that a vote in Parliament before final commissioning, in addition to a decision to go ahead with development of concept and design, is the right way forward. I hope hon. Members will reflect on that when they consider our deterrent in future.

I believe in the deterrence theory. It has worked for decades to protect our country. Although I believe that, I also want to seize every opportunity to negotiate those massive weapons away. To me, the crucial question in this debate is whether the White Paper adds to the non-proliferation talks. Does it make it more likely that we will have a successful round of talks in 2010? The answer is clear. Without doubt, the White Paper is a barrier to progress.

The Defence Committee, which has been mentioned on numerous occasions this afternoon, was right to criticise the Government for failing to have a strong strategy for nuclear non-proliferation. The preparations for those talks in 2010 start next month. There is no indication that sufficient emphasis has been placed on the talks. The White Paper devotes many more pages to justifying why the UK needs to renew its deterrent than to setting out its ambitions for disarmament. What hope do we have if the Government have already given up on those talks in 2010? What hope do we have if this Parliament decides prematurely to renew Trident? The Government seem determined not to give the talks a chance. The message that will be sent to Iran and North Korea by the Government deciding to proceed today is: "Do as we say, not as we do."

Many of those in the Chamber have belittled Britain's role in the world and say that, because we have such a small nuclear deterrent, we have no chance of influencing the rest of the world. I reject that. Britain has a significant role to play in the world, but we squander that reputation on issues such as Iraq and our failure to act on Israel's invasion of Lebanon, as well as this issue of Trident.

What would the Liberal Democrats do? As I said in my opening remarks, the real test in this debate is whether the White Paper furthers the cause of nuclear disarmament. That is why we reject the premature bid to renew Trident. The White Paper clearly states—people seem prepared to ignore this—that the decision on main gate does not need to made until 2012 to 2014, when the first substantial chunk of investment will need to be made. A decision to reject the Government's plans today would not jeopardise the skills base, as many Members have claimed, but it would ensure that we give the talks in 2010 the best chance of success.

The Liberal Democrat view has many supporters. As we heard, former President Gorbachev has made a strong representation to the Government that they should not renew prematurely. Another supporter said:

"There's an argument about whether the replacement is too soon, whether we should be actually putting...off" the decision

"for another 10 or 15 years but actually I think March is unnecessarily soon."

That supporter was Mr. Blunkett, who went on to say to the Prime Minister:

"You are going to be remembered for lots of things...You don't have to remembered for replacing Trident."

We agree.

Like many Labour Members, I came of age politically in the era when issues of war and peace, and our responsibility as a movement and as individuals to make the world a safer place for our children, were at the very forefront of the political debate. A lot has happened in the intervening years, but I believe in the same things as I believed in then.

Today we live in, if anything, a more dangerous world than ever, but if this evening this House takes a vote in principle to go forward with Trident, we will make it even more dangerous. That is partly because the vote will be premature and partly because we will not be doing it on the basis of full information, including scientific information. I refer the House to what Kofi Annan, the former Secretary-General of the United Nations, said on this issue:

"the more those States that already have" nuclear weapons

"increase their arsenals, or insist that such weapons are essential to their national security, the more other States feel that they too must have them, for their security."

Many Members have said that if we let go of our nuclear weapons, other people will not automatically let go of theirs. In fact, we are not letting them go—we will have nuclear weapons going forward into the future. Nevertheless, if we insist on renewing and increasing our arsenal, how can that help with proliferation?

In reading past debates on this issue, I came across a quote from the current Chancellor, then the Member for Dunfermline, East, who said about Trident that it is

"unacceptably expensive, economically wasteful and militarily unsound."—[ Hansard, 19 June 1984; Vol. 62, c. 188.]

I defer to no one in my admiration for the Chancellor. He was right then, and what he said he is even more right today.

I beg the House, even at this late stage, to vote to take this decision when we need to take it, and not prematurely because of other considerations. That would not be a decision to pursue unilateral disarmament. We need to take our decision on the basis of sound information, sound science and a genuine intent to make the world a safer place for our children.

This debate has been prompted not by Trident, as the title of the debate would suggest, but because the submarines are reaching the end of their shelf life. The Trident D5 missile system could continue until 2042. The debate has provided a useful opportunity to take stock of where we stand. We are clearly meeting our treaty obligations. We have also eliminated our tactical missile systems and reduced the number of platforms and warheads. Many Labour Members have argued that we should go further, but the whole point of this debate is that it takes about 17 years to procure a new platform—a new submarine. We need to ensure that we have that ability.

Some Labour Members are proposing that we delay the debate for three years. What difference would a delay of three years make to our ability to predict the enemies that we will face in 17 or 20 years? I do not believe that it would make any difference. Iran has been mentioned a number of times. If we were to reduce our nuclear deterrent, would Iran copy us? I very much doubt it. We would see no change whatever in its programmes.

Will the hon. Gentleman give way?

I will not give way; time is against us.

China was also mentioned. The fact that it destroyed a satellite in space recently got hardly any coverage, but it shows how events are moving forward. We need to be aware of such events and react to them. Looking back in history, we see that the Falklands conflict came out of the blue. Who could have predicted it? More to the point, had the roles been reversed, and Argentina had the nuclear capacity rather than us, would we have dared to march in there? That point was made by my hon. Friend Dr. Lewis in a previous debate. Had Galtieri had the atomic bomb rather than us, major questions would have been asked if we had had to retake the Falkland islands.

The White Paper is about downsizing but maintaining our nuclear capacity. Several hon. Members have questioned the costs involved. I am not a smoker, but I worked out on the back of my virtual fag packet that the proposals would cost every citizen of the United Kingdom 20p a week for the lifetime of the nuclear deterrent. That is cheaper than any car insurance available, and it is a small price tag, considering the catastrophic consequences of our getting this wrong. Many people have argued that we need the money for our conventional forces. They clearly do not know the Chancellor well enough if they think that if we had no more nuclear deterrent the money would go straight into our defence coffers. That would clearly not happen, as I think those on the Government Front Bench would agree.

It has also been argued that we should extend the life of the Vanguard class submarines, but placing them in dry dock, replacing their reactors and carrying out complete refits would cost more than buying new submarines. That argument does not hold water. Nuclear powered submarines, be they Vanguard class or Ohio class, are as complicated as the space shuttle. That is why they cost so much money, and why we have to take care about what we buy. I wonder whether we should be looking to the Vanguard class or the Astute class of submarines for a more versatile platform that can fire Tomahawk missiles as well, as that would provide a bigger threshold for utilising the submarines in a different way.

I pay tribute to the Royal Navy, an organisation that has looked after our nuclear deterrent for almost 40 years. It has been a responsible steward and a reliable custodian. Whatever the views of Members on both sides of the House, I hope that we can all join together to congratulate the Royal Navy on its hard work in providing that deterrent.

I am grateful for the opportunity to take part in this important debate. In the past three months, I have received hundreds of campaign postcards, letters and e-mails that are against the replacement of Trident. To date, I have not received a single letter in support of its replacement. That is a clear indication of the strength of public opinion in my home city of Glasgow and in Scotland against the replacement programme.

I am unconvinced about the massive cost of replacement. In particular, I have great reservations about the accuracy of figures provided to date. Government sources previously quoted Trident's running costs at between 2 and 4 per cent. of the annual defence budget—approximately £1 billion per year. That has been revised upward to 5 to 6 per cent. in the White Paper by my right hon. Friend the Secretary of State. There must now be doubts over whether the global cost figure offered of £15 billion to £20 billion is accurate. Ministry of Defence procurement has a history of exceeding initial budgets. The contract for the new Astute class submarine has already doubled, before a single ship has been launched. Some observers have even put the cost for the full life of Trident's replacement as more realistically between £76 billion and £110 billion.

The factor of fear and uncertainty has been a strong element in the arguments of those supporting a new system. People in Glasgow understood that at the height of the cold war. Given Faslane's strategic importance and the US Navy base at Holy Loch, we felt the real threat posed by Soviet missiles targeted on Scotland. Times have changed. The cold war threat from the Soviet Union no longer exists and therefore the need for new nuclear weapons does not exist.

If we and other countries that have nuclear weapons pursue new nuclear weapons systems, the likelihood of proliferation and of nuclear threats will increase for many years to come. The Prime Minister's argument that nuclear weapons are vital to our national security can, and is likely to be, adopted by other current non-nuclear states worldwide. That view is supported by Kofi Annan, who said at the 60th anniversary of the United Nations that the more those states that already have nuclear weapons increase their arsenals, or insist that such weapons are essential to their national security, the more other states feel they too must have them for their security. Therefore, failure to prioritise real international disarmament negotiations in the near future will only contribute to the ongoing problem of proliferation.

Lord Kinnock, who ended our party's commitment to unilateral disarmament, has said that the Government have failed to make the political, technical or military case for enhancing Britain's weapon system. He is right. The Government have not made the case for the need to replace Trident and for that decision to be made now.

I want to ask right hon. and hon. Members one question: why do we believe that it is right for Britain, the United States of America and Israel to possess weapons of mass destruction and expand their nuclear weapons arsenals, but that it is not right for other nations to develop nuclear weapons? Is it because we have more wisdom, because we are more responsible or because we are a rich nation? If we spent the billions of pounds that we are spending on war and our nuclear arsenal on alleviating poverty, we would live in a safer world.

I am delighted to have the opportunity to make a brief contribution to what has been an excellent debate.

As it was for Ms Abbott, this was one of the most potent and divisive issues throughout my formative political years in the 1980s. I have been struck by the number of Members who have spoken of the issue as a matter of principle. When I resolved my position on the issue, I did so not on principle but on an entirely pragmatic basis. Given that the destructive potential of nuclear weapons is so horrific and enormous, I would have some difficulty in aligning myself with such a principle.

The arguments in the 1980s were threefold in their concerns: the concept of mutually assured destruction; the question of deterrence; and whether disarmament should be multilateral or unilateral. I always felt that that debate was fairly false. I never had much respect for the concept of mutually assured destruction. By the more swivel-eyed tendency to which we have heard reference today, that always seemed to be embraced as an opportunity rather than a threat. But in the context of the cold war, I was prepared to see some force in the theory of deterrence.

We live in a very different world now, however. In the 1980s, during the cold war, I was eventually persuaded to accept acquisition. I did so as a multilateral disarmer: I believed that the only real purpose for which the possession of such weapons could be countenanced was to get rid of them. I think that some justification for that position was provided by the progress that we made in the late 1980s and the 1990s, but, as I have said, the world today is very different. The threats to world security no longer come from superpower blocs; they come from regional conflicts, from rogue states and from cellular terrorist organisations.

In recent years, the arguments in favour of possession of nuclear weapons have become progressively thinner. A number of Members have spoken today about the position of Iran. I think that one of the major motivations for Iran's seeking to become a nuclear power—which, like everyone else, I deplore—is the fact that Israel is believed to be a nuclear power. That is the way it goes. I think it is the major flaw in the argument we have heard from the Conservatives today, the ultimate logic of which is that eventually every sovereign state will have the right, and indeed the obligation, to become a nuclear state.

What the Government are asking of us today is of a different order from what I have been prepared to live with in recent years. They are talking not about maintenance, but about renewal and extension. If we approach the argument on a pragmatic rather than a principled basis, that is where the tipping point shifts. Where will be our moral authority to attend the nuclear non-proliferation treaty talks in 2010 if we back the Government's position today?

If our friend the late Robin Cook were here today, he would vote against the Government. My friend Mr. Devine quoted extensively from what Robin said. Let me quote just a couple of sentences. Shortly before he died, Robin said this:

"Investment in a new strategic nuclear system would be worse than an irrelevance... It is... against Britain's national interests to replace Trident. It is also against our international obligations, notably the commitment in the non-proliferation treaty to proceed in good faith to nuclear disarmament."

The White Paper is full of assertions. Our friend Joan Ruddock made that point. It asserts, as if it were a truth, that

"Renewing the current Trident system is fully consistent with the NPT and with all our international legal obligations."

I simply do not believe that.

When I asked Ministers three weeks ago to supply me with the Attorney-General's advice—the legal advice that allowed the Prime Minister and the Government to say that—I was told that it was confidential. I am not prepared to take these matters on trust, not after Iraq, not after weapons of mass destruction and not after the "45 minutes" assertion. If the Prime Minister came here and told us that we had to invade Iran, do you think the military would go along with that without having sight of the Attorney-General's—

Order. I ask the hon. Gentleman not to draw the Speaker into the argument. That is one thing that I will not allow.

I do not think it possible that the Prime Minister could persuade the House of Commons to embark on a military adventure against another country without tabling the Attorney-General's opinion. I think that this is such an important matter, for all the reasons that we have heard during this long debate, that it is unacceptable for the Government to proceed on this basis.

The way in which the Government have consulted the Labour party has been an absolute disgrace. All the motions that were put before the Labour conference in September were ruled out of order as the matter was going to be referred to the national policy commission. When it was discussed at the national policy commission there was a debate—there always is—but no vote, because under new Labour nothing crystallises into a vote. The only time when I ever vote is when I am here in the House of Commons. That is disgraceful.

I hope that my hon. Friends will, like me, vote for the amendment, and if the amendment is lost I hope that they will vote against the Government.

It is with great pleasure that I say that I—along with, I suspect, several other Scottish Labour MPs—will vote against Trident's replacement this evening. I would vote against Trident's replacement wherever in the United Kingdom it was based, but the reality is that it is based in the west of Scotland and for many decades vast majorities of people in Scotland have made it clear that they oppose nuclear weapons being based in Scotland. I think that that is because they, perhaps more than people in any other part of Britain, are very aware of what those weapons represent. They are weapons of mass destruction that have been designed to target civilian communities and to maximise death and suffering.

We know what the outcome of the use of a nuclear weapon is; we learned that in Hiroshima. The only country in the world that has ever used nuclear weapons is the United States of America. I believe that the primary function of this debate should be to encourage us to do everything we can to make sure that such weapons are never used again. One of the most important things that we must do to make sure that they are never used again is to make sure that as few of them as possible exist in the world and that as few countries as possible have them.

If today we vote for Trident renewal, that must be a breach of the non-proliferation treaty. We are talking about 17 years of development of a new nuclear weapon system at, we understand, a cost of more than £20 billion. That is to develop a new and more sophisticated form of weapons of mass destruction. That is a very serious matter for this House to agree to. If we decide to go ahead with Trident renewal today, we will send the wrong signal to those countries that currently do not have nuclear weapons. What we will be saying to them is that a country such as Britain, which is stable and powerful and the fourth richest country in the world, needs nuclear weapons for our defence. If we need them, we must agree that other countries might also need them.

I welcome the fact that we are having this debate. This is the first time that the Members of the House of Commons have had the opportunity to take part in a debate before such a decision is taken. The Government should be congratulated on that. It is partly because of the strength of feeling on the Labour Benches—

Order. I shall now call the Front Benchers. I call Dr. Liam Fox.

Our debate has been very good, often thoughtful, and at times subdued. It was started in the best possible way with truly excellent speeches by the Foreign Secretary and my right hon. Friend Mr. Hague. Throughout the day, the argument has fallen into several clear areas: the principle of deterrence and the case for possessing any nuclear weapons in the United Kingdom; the timing of the decision to replace the Trident deterrent; the cost implications; and the implications of our decision for disarmament globally.

The bottom line in the debate has been that we live in a risky and unpredictable world. My right hon. and learned Friend Sir Malcolm Rifkind said that threats can emerge and re-emerge, as well as diminish, with little warning. The era of the cold war ended unexpectedly abruptly, and we have no idea where the threats of the future might come from. As