Wow!
Man, Putin is an ordinary man, not a King of Night, mentally controlling the horde of zombies. He can't think for 160 millions of Russians.
Anyway, their borders are still open, anyone who don't agree can go anywhere in the world.
And no, they don't think, that retreating from Ukraine (in its "internationally recognised borders") is better than a nuclear war.
They believe that victory in a nuclear war against the USA can cost them less than one million of deaths in optimistic scenario, less than 20 millions in realistic scenario, and 50 millions in the pessimistic scenario. But it is much better than in retreating scenario, which means losses of twenty millions of ethnic Russians in Ukraine in optimistic scenario, fifty millions killed in the Civil War in realistic scenario, and total annihilation of the Russian nation in the pessimistic scenario of militarisation of Eastern Europe and nuclear war started by NATO's counter-force attack.