I don't think a normal, sanely led US would do that either. More likely the president and joint chiefs would sit in a room and discuss "a proportional response"

I don't think a normal, sanely led US would do that either. More likely the president and joint chiefs would sit in a room and discuss "a proportional response". Turning most of North Korea uninhabitable for generations does not meet that standard. On the other hand, I can see President MAGA saying "turn the entire peninsula into one large crater," a series of Generals trying to talk him out of it and getting fired. An apocalyptic Saturday Night Massacre until he found the just-promoted-ex-Colonel who would issue the order for him.