Getting involved in a shooting war with Russia is a very, very different animal and IMO something to avoid at all possible cost. To be specific, at this moment those (truly awful) costs include the bombardment of civilian areas in Ukrainian cities by Russian forces, which is likely a war crime.
I’m very happy as a U.S. taxpayer to give the government of Ukraine nearly any military hardware they think will help.
But to have formerly-Polish-but-now-American-though-piloted-by-Ukrainian-pilots MiG jets fly from a NATO controlled base to Ukraine to shoot down Russian planes places us perilously close to an actual shooting war with Russia. Such a war could escalate in unpredictable ways.
Vladimir could just be “acting crazy” when he puts his nuclear forces on high alert. Maybe he’s just trying to convince us he’ll do it, so that we do nothing. But how great a risk are you willing to take that he’s only acting?
I do not think this Polish proposal, nor the idea of a NATO no-fly zone (which would require shooting down Russian planes!) are workable ideas. I say this with genuine disappointment for Ukraine. The potential costs are too high.