I don't think the US should take any action regarding NK at all. Why should they? It's nowhere near them.
There are probably people in NK that would support a revolution but most are too deep into the Kim circlejerk. what happens when the US wins? They take over? They install some shitty puppet leader that takes it in the ass from Trump? At this point almost no actual citizens of NK will be feeling "free" if they're even still alive. I think they will be in absolute despair and disbelief.
So it's clear the US doesn't give a shit about the NK citizens. I guarantee the US government sees NK as land for the taking at this point. It's imperialism with more steps.