The short answer is that I do believe it is legally permissible, but it is going to take some work, for this reason. We already have the power when people are trying to return to the United Kingdom. If it is a foreign national, we can exclude them, even if they have lived in this country for any number of years. If it is a dual national, we can strip them of their British citizenship and exclude them from the country. If it is a naturalised Briton, we can, under our new laws passed recently through this House, strip them of their British nationality. But I do believe there is a gap where you have someone born and raised as a British citizen, rather like the individual from High Wycombe we discussed on Monday saying he wanted to return in order to do harm to our country. Of course, the best thing to do is to gather evidence, prosecute, convict and imprison, but there may be occasions when we need to exclude, and so therefore we should fill that gap in our armoury, and I believe it is legal and possible to do it.