Remember the Hermain Cain Award subreddit?

Hundreds of documented cases of people vehemently refusing real treatment for a 'fake' disease, being immensely cocky and belligerent untill very nearly the end, and then, near the end... still somewhere between defiant, in denial, and delusional.

... Those are the private citizens in the US with the vast majority of the guns.

You are completely correct, many areas of the US will collapse into pockets of highly armed, highly religious cults, utterly bereft of anything resembling logic, beyond the sociopathic logic of how to run a cult.

Basically, a couple of David Koresh's for every county. Good luck!