[jhanschoo]

There were a lot of good reasons why Putin shouldn't have invaded Ukraine either. Yet Putin had been making shows of aggression and threats to invade, while securing his political position in Russia for a decade. You can see that Xi had been pursuing similar moves. I'm not sure autocrats see things as reasonably as you do.

[questhimay]

Putin thought the war was only going to be for a few days - according to research by the think tank RUSI, when Vladimir Putin began his invasion, he expected to take control of Ukraine within 10 days https://www.iwm.org.uk/history/how-Putin-lost-in-10-days. He couldn't pull out of the war subsequently in fear of losing control and face. Xi is an idiot, but even he can see his potential downfall, given Russia's failure.