If Homer wants to continue this after the War (ha!) we would see the Soviet domination of Eastern Europe happens in slow motion. Churchill didn't give his Iron Curtain speech until almost a year after the end of the war in Europe. Czechoslovakia didn't go communist until 1948.
I agree with you that the only way to stop it would have been war with Russia. Very, very few Americans had any appetite for another European war in May 1945.
The following facts are all you need to know about how the Balkans turned out:
1. Stalin was going to say anything to placate the west while the war was on to keep the alliance together to defeat Hitler.
2. The Red Army was going to occupy Eastern Europe, and there was no way we could prevent it while the USA, UK and USSR were all at war with Nazi Germany.
3. Once the Red Army was in Eastern Europe, it wasn’t going to leave without being ejected by military force.
4. We were not going to do that. No way. No how.
5. The Commissars followed in the van of the Red Army and imposed the Soviet system.
And that’s the way it was going to be.