I think that's reversed

on the ass part.
A lot of it was bargaining, playing god. The west used the soviets to buy time and not outright support them full time. Allies in name and commerce, but that's about it. Soviets are xenophobic and the west is anti communist. But that said I could see, if Roosevelt knew the bomb was coming, knew he had an asset, he might bargain more. The only problem with the whole premis is that no one card about Prussia.
Poland wanted its renegade kingdom back, the rest of the world wanted its name removed in revenge. prussia just built up so much bad blood that , frankly in 1945, you have 100 years of Prussia poking everyone in the eye and kicking a few square in the balls. People wanted a noose