Putin has become predictable, dropping the threat to go nuclear whenever the war HE STARTED escalates.
Fighting together, Europe, the Nato nations and the U.S. would crush Russia overnight
I've learned by reading tons of book on human psychology, tons of books on crime and murder, that when someone makes a threat against you, whether it's to shoot you or nuke you, You take his threats seriously. It doesn't matter if it's a small pussy man, a woman, a young teen, or a 71 year old dictator.
If Putin is attacked by Nato, and pushed into a corner, I wouldn't doubt he would go, but he would take most of Europe with him by nuking them. You are talking millions of people plus disruptions in food and fuel supplies, perhaps for years to come. Also they would now become vulnerable to other nations like China, Korea, Iran or others.
Several US Congressmen are so stupid that they have actually called for a tactical nuclear war against Russia. They have no idea that all it takes is a couple of nukes to hit American cities, and literally millions will die instantly and millions more will die because of disruptions in food delivery to several states, fuel disruption, chaos among the survivors, etc.
https://www.youtube.com/watch?v=Id9pd8zfQcs&rco=1