This is an extremist view, it's not going to happen, it doesn't even make sense.I'm guessing (who can say, of course) that with the prohibitive secession requirements, what we'll more likely see is a situation in which the states are far more different in their individual laws and environments.
So for example, simply going from State A to State B, we'll want to know if that state is red, blue or purple. We'll want to be familiar with the political character of that state. Possibly even more pronounced than moving from country to country in Europe.
Obviously not what the Founders envisioned, but we've clearly failed them.