That's kind of the problem. He should have been trying to understand it from the Ukrainians side more than seeing the thing as US vs Russia.
It seems a bit of a historical change - in the 19th century view it would be ok for the Russians to get pissed off with the US trying to steal their Ukrainian peasants and associated property. These days you're supposed to let sovereign democracies do their own thing even if they have smaller armies.
Is that how it works? How about letting your ally wipe out a sovereign nation in the ME? Does that count as these days? Or casually kill 2+ mln civilians in Iraq.
“These days” also apply to us and our allies and it is an unfortunate part of how things run.
It seems a bit of a historical change - in the 19th century view it would be ok for the Russians to get pissed off with the US trying to steal their Ukrainian peasants and associated property. These days you're supposed to let sovereign democracies do their own thing even if they have smaller armies.