I think nukes are a last resort defensive measure when other nukes are already flying in air. And besides that they only serve as a deterrent for any attack, the ultimate end of world weapon. I think its foolish to say that even if a war broke out between us and Russia, that it would not just be another ground, air, sea and propaganda war like it was in the past. I think all world leaders know this and are not foolish to press that button which would ultimately mean end of world scenario. I mean we did a preemptive strike on japan before, but japan had none. You think we would of dropped them if we feared Japan having the same types of weapons in their back pocket? I dont think so. Its one thing to weigh the countless lives of other nations people to save your own, but another to weigh the death of theirs and yours at the same time.
Now where it gets scary is people like Kim Jong-Il or even theocracies like Iran. You just dont know if someone like this would just push that button when back to the wall, enemy is at the gate type scenario, kind of like Hitler on his last days in the bunker, you bet your ass he would of pushed a few buttons if that shit was available to him.