[arethuza]

Nuclear weapons are perhaps mankinds most terrible invention - but it is fairly clear that political leaders on both sides of the Cold War were utterly terrified of using them. If they hadn't been invented then I suspect there probably would have been direct armed conflict between the Soviets and/or China and/or the West at some point after WW2, so we were probably saved from another horrific conflict by scaring ourselves rigid with these weapons.

Rational, perhaps not, effective - arguably yes.