You're all forgetting one crucial thing: The Forced Evolutionary Virus.
The FEV is an American creation. It's unlikely that other nations had access to this technology (as it was created as a direct response to the war with China to create 'super soldiers' - China may have had a similar project given the fears of biological attack). The Super Mutants and Centaurs we see in Fallout are a result of the FEV, not radiation. Therefore, no FEV = no mutants.
The rest of the world may be a scorched barren wasteland like the United States, but it would not have mutants (beyond ghouls, which Fallout canon states are caused by radiation).
As such, although China may have some equivalent (we don't know, and are forced to infer), the less developed nations of Earth and those not involved in the Great War "won" in the sense that they don't have to constantly fight with hideous monstrosities.
FEV was NOT in direct response to the war in China, in fact it is debatable if it was at all in response to China. It was a response to suspected Chinese biological warfare, although anyone could have set it off since its origins are unknown, there was no evidence that included them in the original origins of the New Plague. We, also, don't know its extent in other countries, its doubtful that it effected the United States alone.
Yes, the Megaton bomb is most definately the piece that doesn't quite fit. It's an aircraft-delivered nuke (no ICBM attached wink.gif ).
The crashed own ICBM can be explained by, well, okay, some sort of guidance failure or EMP or whatnot. But the MT bomb was deffinately at least *delivered* successfully /albeit it didn't go off/.
Something just doesn't add up. I think that either the US nuked the whole planet (itself included) with the idea of recolonizing it later on (doesn't quite fit with the Vault experiment though - if you wanna do that, you don't go "experimental" on the few you saved) - or, regardless of the propaganda, the Chineese were anything but close to defeat.
It is possible, because of the New Plague American nuclear power was used to contain it, as it was spreading across the United States until the Great War. That is when all died who were hosts.
Just because we don't know the exact details about other conflicts doesn't mean there weren't any. They just weren't relevant to the story of FO1, 2 and 3, so they were not included in the timeline, and will be fleshed out only when the need arises. Emil Pagliarulo talked about how Europe is just as messed up (or worse) than the United States when commenting on Tenpenny coming to the US from England to seek his fortune.
But the thing is, if there were other conflicts I think someone would have detailed them by now. We know, however, FOR SURE that there was LIMITED nuclear exchange between Europe, who was firing them, and the Middle East, who was receiving them and using them on Israel. As far as the timeline from the Fallout Bible states, the Middle East didn't use nuclear weapons in Europe. Just because Europe is "messed up" doesn't mean they were nuked. World War I and II had devastating effects on Europe, for WWI where it was concentrated, such as the trenches of Northern France and Belgium, in WWII there was Total War and everything became a target, military base, city or even small town. I'm sure, especially with the horrible weapons that were in Fallout, damage had to be catastrophic in the Resource Wars, which would have made all of Europe look like Belgium after WWI since everyone warred with one another. Then you have Fallout from the nuclear exchange between the US and China, hell they wouldn't have needed to use that many for radiation to disperse across the stratosphere, that radiation being bad enough to kill plants, animals and people exposed.
I mean that they are in a state similar to the United States as depicted in the Fallout games. There's no reason to assume otherwise.
That doesn't mean, however, there was direct nuclear confrontation, rather, Europe felt it indirectly.
In essence, that's what would have happened. Basically MAD. MAD is what prevented the Soviets and USA from having a full-blown nuclear exchange during the cold war IRL.
Given as it's based from the 50's World of Tomorrow, I'll go out on a limb here. Most missile establishments during the cold war were set with pre-designated targets, so that during the event of a nuclear attack they'd be able to quickly get their pay-load up and away. Theres no reason to assume that such a protocol would have been changed. Now here is the hard part, while the detection of a nuclear launch/attack can happen, it's generally hard to determine the exact trajectory of the nuke(sometimes, launching off the west-coast to China would be fairly obvious, as would be China to USA).
What raises a problem is US military installations, and presumably missile launch sites, within European nations. With that in mind and given the war, the Chinese would have European nations key'd in as targets.
So when a nuclear launch of the scale that happened, it pretty much destroys everything.
This is taking USSR missile protocols, which would have targeted every US Aligned European Nation in the event of a Nuclear Attack, and changing the USSR to China.
Likewise, the US targeted all USSR states, or in this case, all Chinese friendly nations.
However, I don't think it ever says really how the great war started.
Your looking at MAD the wrong way. Just because it was called "MAD" doesn't mean the whole world fires nukes all around, "well, chaps, the world is coming to an end may as well use these damn things," no, you need codes for all of that. We would have used launch sites that were pre-programed to hit Chinese specific targets, exactly as you had said, but not to just knock out Soviet targets as well as endangering Europe unless there was a damn good reason, like Soviet missiles were headed for America. MAD meant Mutually Assured Destruction because a war between any two powers would result in those two powers being annihilated, however, it would also have the side effect, if big enough, of worldwide Fallout, thus the premise of On The Beach. What happened during the war between China and the US was that it created planetary fallout.
So, when we ask ourselves who objectively won the Post-War, without a detailed picture of the rest of the world, no one did is the most credible answer that one can come up with when everything is taken into account.