The next seven countries combined (the next eleven, in fact) are all in green in the above map. #12 is Canada, and every other country is either supporting this resolution or abstaining. The US could well win a third world war but it wouldn't happen the way you say. Nukes won't be used in conflicts by nation-states, only (and hopefully not) by rogue groups that get their hands on one. Nukes are a deterrent nowadays rather than a weapon.