Political entities and boundaries come and go. They should never be frozen in history, because so many are accidents of history anyway. Should powerful empires, crazy-quilt conglomerates - China, Russia, the EU, maybe the USA - devolve? Why not? Would it be worse, or better?
In the US, I can easily see California and Texas as their own countries. They were never envisioned at the beginning anyway. Either one would be more of a nation than Canada, Australia, or Austria. Smalleer governments are more accountable and more responsive.
Even Spain could break into its constituent parts if the empire permits a vote.
Dismantling Empires Through Devolution - Democracy is not the most potent political force of the 21st century.
Should the American civil war have been subject to a confederate referendum first?