It's been almost 20 years since I studied any of that, but those proxy wars in far-flung places did directly challenge other powers because of the Domino theory

I don't necessarily agree with Morgenthau and Carr as I think most IR Theory is bullshit made up by academia... particularly the stuff around how players "gain power"

So I make my own argument which mostly hinges on the idea that two powers really means "my power" vs. "everyone else" which is not a recipe for peace