[bluedino]

Imagine if different areas of the United States still spoke the languages of first-generation immigrants.

You'd have the French, German, Dutch, English, native tribes, Spanish...

[HarryHirsch]

Not the United States of America, but the United States of Austria were actually a serious proposal: https://en.wikipedia.org/wiki/United_States_of_Greater_Austr...

The issue usually isn't ethnic tensions, it's usually disenfranchisement expressing itself through nationalism.