@pintohoo; it appears that Putin is now playing Nuclear Chess with NATO, albeit in a shadow-boxing manner that could get out of hand.
IMO the real game is the reduction of Eastern Ukraine to scorched earth - the flooding caused by blowing up dams and infrastructure annihilation maybe even including the destruction of the nuclear power plant together with land mines would render the region a worthless and toxic time-bomb for decades ... literally a 'No-mans' land!'.
If Russia continues with its scorched earth practices there'll be a large buffer zone between it and hostile NATO countries which would likely be exactly what Putin and his henchmen have wanted all along.