When you have to make excuses for the government you usually get testy with people. Have you noticed that?
The phrase "revolutionary power" was used in the article you found so enlightening, with which you began this thread. Our revolutionary power is based in principles, not in conquest. I can list you more than two dozen empires without breaking a sweat, but the nations whose authority comes from principle are tiny in number.
Principles are principles are principles. They apply across the board.
There's a lot of brutality that could have been avoided if we had acted toward the citizens of other nations the way we are constrained to act toward our own.
It is kind-of fun to watch you twist yourself into a pretzel to justify Yalta, though. Care to try for a Soviet trifecta? Hungary and Czechoslovakia might do it.