Or the current regime will collapse. That often happens with large scale defeats, especially without a democratic outlet for internal change within the system.
The worst it will happen to Putin is that he'll be locked in into Russia and have to kill more and more Russian people.
The reference to MAD makes sense only in the context of foreign armies (and with the M only those of major nuclear powers), but if you look at the two immediate predecessors of the modern Russian Federation (the USSR and the Russian Empire), both fell without a foreign army entering the capital, and are hardly unique in history in doing so. And to the extent status as a major nuclear power is relevant to that, the USSR had it just as much as the Russian Federation does.
Germans finance his war efforts with billions of euros and drag their feet on arming Ukraine.
Europeans generally pressure Ukraine to surrender.
Why risk it? Just wait, time is on his side.
Save for Netflix not working anymore, life in Moscow is even better than pre-war.
Ukraine is getting heaps of weapons and decimating Russian logistics and command and control with it. Enough that even the Russian propaganda is complaining about it.
The subthread was discussing what would happen in the event Russia was forced to abandon the invasion, if you want to object to discussing that possibility as reasonable, the place is several posts upthread.
(Also, Western aid delivered since the major escalation by Russia this year has been several multiples of Ukraine’s annual defense spending and a sizable fraction of Russia’s annual defense spending. It is not “weak” arms supplies by any reasonable standard.)
Same hubris that lead to defeat in Afghanistan
Historically—not universally, of course, but frequently enough to be noteworthy—people have been observed to be displeased with leadership that unproductively transforms large numbers of their youth into corpses.
Besides that soldiers send a lot of stolen goods back home. There was an infamous video from the office of a transport company with dozens of soldiers sending loot like washing machines.