The Russians and the Ukrainians in a Third Rebellion

The Ukrainians have already soaked up a lot of the military equipment and ammo that the Russians had stockpiled since 1945. So, what we're looking at here one way or another is an extreme breakdown of the security order. Either the Russians win, which means Ukraine ceases to exist and we're in a direct nuclear confrontation between NATO and Russia. Or the Ukrainians win and neutralize Russia's ability to control large chunks of its own territory, likely heralding the disintegration of the Russian state itself.