well, two things. They were commies, and that alone was a great part of the antipathy towards us, maybe the greatest part....and that would have been a factor even if we had moved in with them during the war. A clash of philosophies was going to happen no matter what.Yeah make no mistake - WW2 ended the Great Depression, I think any rational person realizes that. That said, the programs he implemented stopped the bleeding and at least put us in a position to be the manufacturing superpower we became in the late 30s and early 40s.
Russia's mistrust of us mostly stemmed from us not helping them though. Stalin was always a little leery (as he was with everyone) but him begging us to fight on the Western front and us telling him no for 2 and a half years was really what started the Cold War. It was genius on our part, the Japs were our immediate threat, Hitler was Europe's problem for the time being.
And yeah, we could have absolutely wiped them out before they got the bomb (and after, but it would have been a bit more difficult)...but the last thing anyone wanted was another World War. Our focus was making Western Europe capitalist.
The other thing is that wiping them out might not have been the cakewalk you maybe think it would have been. We were still fighting the japs..anese, and Russia was just getting cranked up as they rolled into and over Berlin and that side of Germany. There would very probably have been some of the toughest fighting of the war, a lot of house-to-house kind of stuff. And we would NOT have used the bomb on them.
In our favor...we would not still be sending them materials and weapons, etc. Against us...overwhelming sentiment at home to get the hell away from waging a war.