Actually, I think the breakup of the US is a normal part of its evolution. And the same goes for every other large country presently extant.
The time of giant nation-states is over.
The concept is hardly original to me. Jefferson even wrote about it; I haven’t been able to find the reference for this, though. I’m not an early-American specialist.
Two forces dominate history—Balkanism and Imperialism , One is a break up into smaller and smaller states, the other groupings into large mega states. Now we are in the Balkanization phase, then we will enter the Imperial as new large states appear—these will not be UN Global states but good old fashioned head busting imperialism. Hard to say how it will play out and what core states will be the builders of Empire—It takes a stable nation and a powerful charismatic leader. Not a lot of Napoleons around these days—but that may change. I believe China will not be one—too many internal problems, Nor will any south American Nations. Maybe Germany, maybe Russia, maybe India, perhaps South Africa, maybe Japan. We shall see.