If Hitler had not started Barbarossa, politically it would have turned interesting to see what position the USSR would hold within a couple of years when the US would finally enter the European war one way or the other. (And without the US there would be no invasion of the continent.)

The Russians were involved by supplying Germans so would Roosevelt consider them the enemy on that basis despite Churchill´s belief that the war in Europe could be won only by getting Russia to war against Germany. So what side would Stalin pick? Probably trying to stay neutral but could he stay that way?

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