When I was in Germany their Prime Minister (Gerhard Schröder) was deeply invested with crony capitalist Russian businesses. He was a big fan of Vladimir Putin and used some (valid) criticisms of George Bush and the Iraq war to push germany more towards dependency on Russian energy. You should start with that before railing against American's.
I don't think we would do this, we have enough problems of our own that both, take precedence over Ukraine, and are frustrated by the Ukrainian situation. Looked at in a certain light, we're incentivized to stay out of this. That said, our policymakers have shown themselves in the recent past to be, well, not the brightest bulbs. So anything is possible.
But this just smells like different nations in Europe going rogue. Probably good intentions, but it strikes at the national interests of other European nations. It's an escalation as, previously, dual interest assets were not targeted explicitly for the purposes of keeping all western nations aligned.
They are playing with fire at this point. I hope we don't get dragged down with these people.
This to me seems the most likely. If they are afraid EU countries, like Italy, which many of the leaders of the party are against the war in Ukraine, might not support the war, freezing them out this winter might push them to change their mind.