The Russians have no illusions about China and China try to take part of Siberia there will be a nuclear war.
If China has to nuke Russia in order to restore Chinese rule over Chinese territory then they will.
Better Russia should give these lands back to China instead of risking WW3 over them! Or maybe they could negotiate over how much land China will take for now. Oh, and I imagine China will want to denazify these areas. That’d be sensible.
Eastern Russia is not populated simply because no one can make a living there. The coastal areas are all that is worth a damn.
As China transitions back to by the book Maoist socialism, the actual outcome becomes less and less certain
China that was, isn’t