Who won WWII?

[Slyspy]

That's a good comparison, because you slighted the UK as well as the USA! The UK's victory in the napoleonic wars was engineered over a long period of time, was a masterpiece of planning and realpolitik, and led to the British basically ruling the world for 100 years afterward. If that doesn't merit a leading role in the discussion, I don't know what does. The same can be said for the USA in ww2.

The questions of "who won the war?" and "who won from the war?" are not the same of course. In general, though, the nation which does most to win the war is that which acts a paymaster to the rest.