[The Duke]

"I served three years on the Cold War's front lines in West Germany, near the Fulda Gap (V Corps) in the early 1970s, so I know a little about nuclear threats and counter-threats."

And I worked in a hollowed-out mountain for three years, simulating Armageddon for some very serious people.

[BroJoeK]

The Duke: "And I worked in a hollowed-out mountain for three years, simulating Armageddon for some very serious people."

Then you well understand that MAD only deters if everyone on both sides believes it.
The moment we are perceived as weak in will or capabilities, deterrence disappears and Vlad the Invader, or CCP's Xi-snake will do "whatever the h*ll he wants".