Originally posted by Tavenier
I don't know if the chance of a nucleaur war would be bigger. A balance of power is better with more participants. Although we can now say that everything went quite well with 'just' two superpowers. But when living in those days I wouldn't know what I prefered.
A balance of power is more likely to move into imbalance the more participants there are, which can only happen when some are waxing and others waning (late 19th century, breakdown of British hegemony, rise of Germany, Italy, Japan -- lots of wars). It's no coincidence that huge general wars do not tend to break out when the number of powers has been greatly reduced, and one or two predominate (post-1815 period, post-1945 period*). And those powers will tend to turn conservative, becoming more interested in protecting what they have than in any future expansion (which would require challenging the other power), reducing the chances of direct conflict. As for nuclear confrontation, that was in absolutely noone's interest, and the threat was in fact very low throughout the cold war.
Now, however, with the threat of proliferation, the possibility of "regional" nuclear exchanges, or of terrorists obtaining WMDs...
Back on topic, was the war "necessary?" Well as others have said, perhaps no war is
necessary. I'm skeptical of the "red menace" conspiracy theories (Stalin was an opportunist, not an idiot); Germany and Japan were the real threats, and with the absence of a real, enforceable collective security organ in the 30s due to the unwillingness of nations trying to fight the depression to commit themselves to international affairs, their aggression probably could not have been prevented. And one can argue with the tactics involved, but neither Soviet nor American aims would have been well-served without the complete elimination of Germany and Japan, important industrial centers and potential military competitors whose allegiance, to one side or the other, would be important later on. Ultimately that's why I don't think either the Russians or the U.S. were interested in negotiations with Germany or with supporting some kind of revolution or assassination to end the war early. I recently read a fragment of an American military document from 1943 or '44** indicating that even then, U.S. officials were thinking in terms of a "race to Berlin" in which the real competitors were the U.S. and the U.S.S.R. Something similar can no doubt be said of the situation with Japan, considering the timing of the atom bomb attack to coincide with the Russian invasion.
* -- of course, I'm talking about wars between significant world powers. Non-powers, particularly in strategic or raw material producting regions, continue to be victimized regardless of the status of the balance-of-power system.
** -- I'm afraid I don't have any more info on the source as I don't have the book in front of me, but you'll find it in T. McCormack's "America's Half Century," a cold war rundown.
