Rational behavior in some situations? Mutually assured destruction’s deterrence isn’t very effective if one side is known to be hesitant to launch the nukes. It’s been argued that MAD is what’s been keeping the world relatively peaceful for the last 75 years, no mass conflicts since WW2!

One of my criteria for presidential candidates is that they seem willing and able to push the button when previously stated red lines are crossed, or at least are perceived to be the type capable of it. One of the characters I’ve hated most in all the books that I’ve read is the woman in The Three Body Problem who jeopardized humanity by being too soft to hit the MAD button.