A few observations I've not seen made elsewhere.
Ukraine is a mirror image to the Monroe doctrine. As the USA claims nothing happens in north or south America without their consent, so too is Ukraine in Russia's sphere of influence. I'm not saying this is right, or just. It just is what it is.
Major events in human history have a long reach to dominate the shaping of events afterwards, but not a full century after. It's been more than 80 years since WW2 ended and its historic influence is almost played out. The USA signed up to keep the fascists down and out, save western Europe from economic collapse, and to hold communism and the Soviet empire at bay. Today? Western Europe's thriving. The Chinese, and Vietnamese, are still communists (depending on who you ask) but they're not interested in spreading communism and are no threat to Europe. The reborn neo-Mongolian Tsarist empire of Russia is pretty nasty, sure. They're also an entirely European problem far outside the context of anything the USA signed on for. Even more so as they are a problem Europe can handle on their own if they want to.
Yeah, if. Yesterday, Nato was meant to hold the line just long enough for the Americans to show up again in force while paying for most of it. Today, Europeans think Nato means America pays for it all. Poland is the only Nato member with a realistic attitude demonstrated by spending what it takes to build the largest and most modern fleet of armored fighting vehicles in the world. A few other Nato members have said, "Sure! We get it! We'll pony up and pick up the tip." They made very modest increases to their defense spending in the hope this would bring America back to the bar and pay for the drinks. Sadly, America is not cooperating. Turns out the Europeans still need to greatly expand their military establishments. That means far larger armies, the creation and maintenance of enormous munitions stockpiles, and the building of expensive and extensive weapons manufacturing and related supporting infrastructure. As in more than three times the modest increases by everyone, not just the thrifty adventuresome few.
Also means Britain and France must expand their nuclear stockpiles. Yeah, now we're talking expensive. Ask them about paying for that and one quickly suspects they're praying Poland decides to go nuclear in the near future.
Europe will continue to deliver platitudes about the need to defend Ukraine. Watch what they spend.
As for America, their sights are on China, and the next show down for the Pacific. The air is full of talk of the Quad made misty with wild eyed dreams of a Seato reborn where everyone pays their fair share.
Ukraine? No. Otherwise, place your bets.