Like yeah, we all know that communism defeated fascism in WWII, but that was only after a lot of war & genocide had already transpired.
I'm interested in the counterfactual, in which it never got to that point because the Nazis and Italian fascists were prevented from ever acquiring power to begin with. What would that have looked like? What would have been needed for that to happen?
The Black Hundreds in Russia? Not up on my history at all, someone with more knowledge would be better here.