FIFY. You're slipping
As for the rest of your theory- Ukraine v Russia has been brewing longer than Biden or Trump has been at the helm and some would say that certain US agencies were there driving the shift back then. I think it's a matter of US foreign policy trying to prevent Russia from taking back their old USSR borders and Russia being pissed off that we're doing it.
Should we even be sticking our nose there? I dunno, but at some point the conditions were ripe for cold-war era USSR to be a threat to the US, and perhaps it's best to prevent those conditions from happening again. Keep in mind that before tensions in Ukraine were a thing, Russian bombers were still probing US fighter response times near Alaska without provocation.