Point of this thread is kind of dumb considering that if WW3 were to happen, it wouldn't be continents vs continents. It would be certain countries vs certain countries. There is no way USA, the UK, Japan, South Korea, Australia, etc, etc would be fighting against each other...they'd all be on the same side. So in a more accurate response to the thread, I would say whoever is allied with the USA would win. Considering the USA spends more on its military than the next several countries combined. And considering that the USA has more projection power than almost the entire world combined. Yeah....it really is no contest. Unless of course everyone just nukes each other....then everyone would lose.
---------- Post added 2012-12-30 at 10:44 AM ----------
And then you would die from the world being thrown into a nuclear winter. You still die.
Kinda on-topic: I was thinking I heard somewhere once that it would only take as few as 10 nukes going off in rapid succession to plunge the world into a nuclear winter. Does that sound right or was I just dreaming it?