Those countries should have been vetoed out of NATO after considering the look of the situation to Russia. There should be no countries aligned with the US military within a very wide margin of Russia, and the alliance should have stopped expanding north-east when the USSR fell. Militaries deal in present realities, not how voluntarily people signed up for military alliances. Russia should not have to wonder how trustworthy the US is being (spoiler: the US is not trustworthy although they are a lot less capricious than the average nation). It is easy to see why they might have felt pressured to invade after the Ukrainian revolution, without needing to resort to "well Putin must just be that evil & crazy!".
>There should be no countries aligned with the US military within a very wide margin of Russia
Why, just because Russia wants that, so that it's free to invade it's neighbors? People in Eastern Europe do want to be part of NATO for a simple reason - not to have to worry about their big neighbor deciding that it's time for a "liberation". This is not about aggression, this is about not being invaded.
Not a great analogy. Ukraine had not joined NATO, and there seemed to be no prospect of it.
The countries that actually did join NATO appear to be safe from Russian invasion. If the Baltic states hadn't been allowed to join NATO then Russia might already have a land bridge to Kaliningrad and we'd have lost some more liberal democracies.
I wouldn't mind if it was a military alliance of Russia neighbors and it disavowed the use of nuclear weapons. Then it would truly make the world safer, IMHO.
It's ex-eastern bloc countries willingly joining the alliance to be protected from Russian aggression. If Russia did not have a long history of invading their neighbors, there would be no need or will to join the alliance.