Post 2020 and the Covid19 epidemic the states couldn't decide on how to isolate, lock-down, and re-open. So they all split into "regional state medical associations" or something like that i don't remember exactly. This was not state secession or 'semi-autonomous region' recognition etc. But it was a clear and recent example how material situations can suddenly motivate or force a re-organization on national institutional scales. To spring-board off this we can theorize; if there was another "disagreement" between states on how to react to a new situation (medical or other) that they would make similar moves, such as re-organizing into state coalitions, or perhaps smaller break-away regions. Lead by whoever is sitting leadership at the time.