The US has not invaded a democratic, friendly country in several generations.
> If you don't treat similar situations similarly, the only option on how to act is in your own interest.
That's ridiculous. That's like saying if you can't save everyone, you shouldn't try to save anyone. Doing the right thing in Ukraine does not require doing the right thing everywhere.
There's no point in my arguing with you because you are starting with a moral premise -- black-and-white whataboutism -- that is both extreme and uncommon. Governments should do what their citizens vote them to do, and most voters/human don't agree that we should ignore Russia invading Ukraine because we don't support regime change in Turkey.
Applying your morality uniformly, Europe should either go on a worldwide rampage and try to topple every moderately corrupt leader (including those, like Zelenskyy, who were elected democratically), or they should allow Russia and China to build empires by toppling democracies. It's one or the other -- you can't be inconsistent, right?