Putin will drop the bomb !

Putin is an insane egomaniac, and no logic helps, nor does raising the Ukrainian flag in front of the German Reichstag . This man thinks in his own categories. If anything, China can still offer him a way out of the self-imposed isolation. Any further escalation will leave us all with the sentence: we would never have thought of that. The question is: 
How could Hitler have been stopped if he had the bomb back in 1939 ? This is the situation we are facing right now. 
No alarmism ! In his madness he will always be one escalation step ahead. 
De-escalate ! 
NOW !