Jeremy, you said in a post, which I can't find, that Ukraine tried neutrality but that it didn't work for them. Putin recently said in a meeting with African leaders concerning peace proposals, that "Kiev obtained its independence during the dissolution of the Soviet Union, based on the declaration of independence, and this declaration states clearly that Ukraine is a neutral state. This is of principle importance to us; it is not quite clear for us, why the West started pulling Ukraine into NATO", adding that, in Moscow's opinion, this is what poses a fundamental threat to Russia's interests.
What is a threat to Russian interests, currently, is the lack of a defensible land border. Putin, and the Russian military, remain publicly committed to the idea that 'the West' has eyes on invading - whether that's a genuine (but ridiculous) belief or just posturing isn't clear. Therefore his policy, as has been Russian policy on and off for at least a century, is to create a buffer zone around 'Mother Russia' by subjugating or occupying neighbouring territories to create a more defensible barrier.
Ukraine, recognising this, looked for options to defend itself, and NATO was the obvious partner to move towards. NATO isn't pulling, Russia is pushing and has been for some time.
O.