All former prime ministers have supported an "independent nuclear deterrent", including David Cameron. Only one, James Callaghan, has given any insight on his orders; Callaghan stated that, although in a situation where nuclear weapon use was required – and thus the whole purpose and value of the weapon as a deterrent had failed – he would have ordered use of nuclear weapons, if needed: "if we had got to that point, where it was, I felt it was necessary to do it, then I would have done it (used the weapon) ... but if I had lived after pressing that button, I could have never forgiven myself." Denis Healey, the Secretary of State for Defence and "alternate decision-taker" under Harold Wilson, said that in the event of Soviet nuclear weapons attacking the United Kingdom and the Prime Minister had been killed or incapacitated, he would not have ordered a retaliation.