Regardless of Putin’s power stronghold, invading Ukraine was a collective decision. War entails mobilizing an entire bureaucratic apparatus manned by some of the most intelligent people on the planet. Notably, our space race and cold war adversaries were Russian: a very smart, capable, and educated people. Presumably, the Ukraine decision was not made on the simple whim of a mean, power grabbing dictator: Evil Putin as the media simplistically portrays him.
Is it possible that Russians based this invasion on some rational reasoning? The notion of Ukraine joining NATO, nuclear weapons at their doorstep, or a cross-dresser President at the helm might have triggered their existential fears. Since Ukraine is to Russia what Cuba is to the USA, a 5-minute nuclear missile flight time would have been a relevant factor in their situational assessment. Imagine that.