Everyone I talk to says the military will refuse the order of a crazy man.If several bouts of mobilizations (he's gonna have more) won't provide him a victory, more likely is him using tactical nukes. It's just a question where he would chuck them. Naturally, apparent choice is into Ukraine, but actually I think he'd be gunning for a sparingly populated yet tactically relevant area in Poland and/or the Baltics. A show of force, like hey look what I'm willing to do...then he's hoping for a harried peace deal in the UN in lieu of nuclear escalation.
However, the military is completely cut off from communication, and are brainwashed. Even the average russian citizen is in favor of dropping nukes on ukraine. Several of putin's advisors and heads of state are calling for nukes or for putin to step down(and probably get a bullet). And he hasn't at this point. So that tells me that a) putin doesn't want to and b) if putin is replaced, it probably won't take long for someone to push the button.