> Putin hates democracy and fears that a successful democracy next to his door will trigger his fall.
That sounds ridiculously simplistic and caricature-esque. Besides, the Baltic states and Poland have been fairly successful democracies since the end of the Cold War, they all directly border Russia, and Putin hasn't done much about that for the past 20+ years.
> He also has an obsession that Ukraine is not a real country and that it's essentially a part of Russia.
Yes, I fully understand the history of Kyivan Rus and the shared Slavic history of Ukraine, Belarus and Russia. But again, "we all used to be the same people 800 years ago" seems like even more of a really stupid reason to invade.
To put my argument in a different context, since the end of the WWII large powers have at least tried to put up a semblance of a noble argument when invading another country. In the US in Iraq in 2003, WMDs may have been bullshit, but it was at least proposed that "we are invading to defend ourselves". I don't even feel like Russia is trying very hard to make that argument - they're doing it a little with the false propaganda of genocide against Russian speakers in the east, but in general it's like Putin's not even trying to hide his "Tough shit, we're a bigger country that can take over a smaller country if we want to" rationale.