There was a series of short stories out about a year ago. I have it saved somewhere but forget the title. The gist was that, after the balloon goes up and DC clamps down on an increasingly-dysfunctional US, a massive, well-equipped and highly technological army suddenly appears and moves out of the “Great Western Redoubt”, and pushes down I-5 clearing out the entire west coast. They have lists of “conservatives” and “liberals”, and the libs are summarily evicted from their houses, dispossessed, and escorted South (eventually across the border into Mexico).
Rather than give up on the Cradle of the US, I’d much prefer to see Shay’s Rebellion v2.0, where the lib governments of New England are disenfranchised, and the leftists rounded up and pushed into enclaves somewhere else, maybe NYC or better yet, the ruins of Detroit.