Earlier quoted context omitted.
There is a mechanism for dealing with this: secession. A lot of violence will be saved if we start agreeing to amicable divorces. I don't expect us to do that, so, sadly, I expect a lot of violence.
If states secede why not parts of a state? Why not cities? Why not neighborhoods. You're pretty much advocating the end of civilization and the return to tribal groupings. But tribal warfare was actually much more violent and unstable than the nation state.
Territories with strong social identity would maintain political union, territories with weak social identity and severe political disagreements would split. As much as is possible, no one is ruled by people they hate.
https://en.wikipedia.org/wiki/Subsidiarity
We are taught this is impossible because the ruling class, who favors ever more centralization, wishes that to be so.