2. In a way, this is the problem with FDR's role in American history. Just like the blonde, he had a number of attractive features....but one glaring problem: a misunderstanding of geopolitical reality.
'It's always somethin.'"
a. That 'somethin' resulted in the United States becoming, for all intents and purposes, a vassal of the Soviet Union. It caused the Korean War. It is the reason that China became Maoist, with 75 million deaths. And if the United States ever goes to war with China....the 'somethin' will have been the provenance.
...and are willing to ignore 'somethin'......
The whole problem with your PRemise here is that you overinflate the importance of the US in the ultimate victory against the Axis.
The USSR did most of the "Heavy Lifting", as Cheney liked to use to say.
By contrast- The USSR lost 20 million people defeating Hitler. The US Lost 450,000. There was a death struggle, to be sure, between Communism and Fascism, but Capitalist Democracy was just holding the coats.
At the end of the war, the USSR and US were the last men standing. The United Kingdom was on the winning side, but with the promise to the people who had fought to save it that the British Empire would end. (Again, comarisons, only 500K British died fighting the war, but over 2 million Indians and Pakistanis, on the promise of Indian independence.) France was shattered.
Let us take your example of the Korean War. Contrary to popular belief, Atom Bombs had little to do with Japan's surrender. What forced the Japanese to surrender was the USSR finally entered the Pacific War and rolled up their Kwantung Army in Manchuria in two weeks. (Again, all those weapons eventually ended up in Mao's hand. Stalin already had plenty.) the only reason Stalin didn't take the whole of Korea was because he didn't want a dustup with the US. NOthing was really going to stop him if he wanted to in 1945.
Now, besides the usual hystrical , "Communists killed a Gazillion people" nonsense. (Nope, sorry, not that many, and PEOPLE killed people, usually over reasons that had little to do with politics.)
The fact is, China was not ours to lose. Mao won because the Chinese people wanted him to win. It's why they still revere Mao even after they've concluded Communism isn't such a hot idea. Vietnam was not ours to lose. Those people got fed up with colonial domination, and that was it.
I do find the amusing notion of being a "Vassal" of the USSR funny. I had a talk with a British person once who felt the nation that really took advantage of WWII was the US. They charged the other allies exhorbitant amounts for war materials during the war and consumer goods after the war, and moved into the vacuum left as the Colonial Empires fell.