Dr Julian Lewis: I can, perhaps, throw a little light on this matter. In the late 1970s, the Government signed positive and negative security assurances that committed us to giving assurances that we would not respond with nuclear weapons against countries that had non-nuclear mass destruction weapons, but no nuclear mass destruction weapons. I hope that my right hon. Friend [Sir Geoffrey Johnson Smith] is making the point – which I intend to emphasise if I am fortunate enough to catch your eye, Mr Deputy Speaker – that those assurances should be rescinded, particularly in the light of the fact that biological weapons have not been abolished, although that was supposed to have happened in 1972.