If a shoe fits on one foot, it fits on the other too. Aka the "M".

The "Russia is a madman, but we're not" is... difficult to square logically and historically.

Beneath all the political and PR charades, during the Cold War the Soviet Union was generally as terrified of the West pre-emptively nuking them as vice versus.

Presently, it is not during the Cold War. The idea that Putin is terrified of nuclear annihilation is ridiculous.

Just speculating: I'm fairly sure Putin knows that the West won't do any nuclear first strikes.

But if he tries anything even remotely nuclear, the West would just annihilate his empire. And the West wouldn't even need to go nuclear.

(Especially if the West got serious and opened the money floodgates. I suspect even in the current state of the Ukrainian war, if they offered any Russian defector 100k USD and a new identity under a EU passport, they could meld away the Russian army fairly quickly.)

Russia would most likely also lose the tacit support of India and China, if the bear were to use nukes first.

Those who had access to classified information did not think Russia was bluffing. They are acting like they think MAD is still in play - while they are not talking and may have other reasons for acting like this, I think it is safe to assume MAD is in play.