I would like to make a little progress before I take more interventions.
I know that there are a number of serious and very important questions at the heart of this debate, and I want to address them all this afternoon. First, in the light of the evolving nature of the threats that we face, is a nuclear deterrent really still necessary and essential? Secondly, is the cost of our deterrent too great? Thirdly, is building four submarines the right way of maintaining our deterrent? Fourthly, could we not rely on our nuclear-armed allies, such as America and France, to provide our deterrent instead? Fifthly, do we not have a moral duty to lead the world in nuclear disarmament, rather than maintaining our own deterrent? I will take each of those questions in turn.