The real issue is Putin honestly believes Russia gets to unilaterally determine which countries are legitimate, and has the right to invade them, steal all their property, and kill whoever they want based on whatever bullshit justification they make up.

I can't tell you how many times I've to a Russian who was genuinely struggling with the basic concept of "You can't break into your neighbor's house, murder their family, and steal their TV just because you said they were gay Nazis or something."