the us is a cauldron of secessionist sentiment.
Western WA wants to dump Easter WA (and vice versa), Northern CA /southern CA, The East the South, the North, chunks of OH, NE wants to lose Omaha .... but in my experience, these moods generally fade.
NoCal wanted to badly dump SoCal as the politics of SoCal had become very Orange County Conservative, they were winning things like the Gov mansion and the WH.
And now they have Gov Jerry Brown.
WA recently legalized pot and gay marriage. This is the state that defeated its own sitting senators Jackson, Magnusen and House Speaker Foley ... all in a fit of east WA conservatisim (this is simply the act of taking considerable power and deciding to give it to somebody else)..
But the new WA and the new CA are rather breathtaking in the direction and positions they have taken. All absent secession.
The state of WI ((which along with MN is the real home of liberal thought in the US) currently sports the likes of Paul Ryan and Walker. The place that gave us things like Feingold and Nelson and Black now foists this stuff onto the stage. But it will pass.
I am inclined to think the Federalism will survive, I think of the story of the transgender mayor in OR:
http://en.wikipedia.org/wiki/Stu_Rasmussen
this is a pretty conservative neck of the woods, and when he won the hate mongers showed up with all of their devil and brimstone and stuff and all their certainty about god hating them, america, gays and so on.
The thing is this: that small conservative town had issues with Stu, but they had no place for somebody else coming in and telling them about their own. So they counter-protested, the whole freeking town did opposition rallies, parade, and protests .... and they did it in drag.
I kid you not, that town stood against the others, stood there in drag, --- drag, a concept they individually personally detest.
The US has don't tread on me, but it rarely expresses beyond a post code (zip code).
So the secessionist thing is real and all over the place, but it is much less regional, and much more county by county.
There is no nation, but there is definitely my town. And don't screw with my town.
SO in the end I don't think catastrophic division is in the cards, the units of identity are considerably smaller than that required to affect such radical realignment.
Visit San Antonio and Dallas and then talk to me about "Texas".