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Trident

For that very reason the White Paper goes into the different systems in some detail. I agree that one of the issues is: should we stick with the submarine-based system, or should we move to some other type of system? All I can say is that, for the reasons given in the White Paper, the submarine-based system is, in my judgment, the most suitable form of deterrent. One can go through the other options, which are all well known. In the debate over the coming months, people can canvass all those different options, but the difficulty is that an aircraft armed with cruise missiles is far easier to intercept and the cruise missiles go at subsonic speeds. In any event, in terms of cost, I am advised that the aircraft would have to be specially designed and that is an enormously expensive undertaking. We could have a surface ship armed with Trident missiles, but that is an easier target. Alternatively, we could have land-based silos. It is worth pointing out that America, for example, has land-based silos as well as air-launched and submarine-launched missiles. Its land-based silos are situated in a vast territory—a huge area can be used for that purpose. I do not think that that is practical for us. Therefore, there are very good cost reasons why it is best to stick with the submarine-based missile. This is precisely the type of issue that the next few months will allow us to consider. The White Paper goes through those options in detail—this is why I wanted the White Paper—so that the perfectly legitimate questions that have been raised can be answered.