>>26555
Your example is completely misleading: you forget that the USA not only conquer Mexico (and the rest of Central America), but adopt much of the superior Mexican culture as their own, Mexican art, literature, religion and philosophy; the American intellectual and political élite speaks Spanish as fluently as English; New York City, Washington and other cities have an important Mexican minorites now. And this situation lasts for centuries, so that we can speak of a true Mexican-American world and culture. Not so clear-cut now, eh?
Moreover, the government doesn't ever flee: sure, Canadian natives from as far as Greenland are pressing on the borders, but in fact the capital is moved to New Washington, in the Spanish-speaking (pleb-wise) half of the Empire, to face the menace of the communist Tawantinsuyu. All is done calmly and with all the proper ceremonies, and the capital could have as well been moved to Los Angeles—like it has in the past. Little changes for everyone but the somewhat pissed old Congress, that had little influence anyway.
Americans from Panama to Augusta know their President and Caesar has only relocated his seat again.
After more than a century, though, the Northern United States of America (the state has been split, if only in its administration, and has two equally American Presidents) is ravaged by the redskin hordes, while the Southern half resists.
Again centuries pass, and while things have naturally changed in what remains of the US (for example, while the North has neglected Spanish, once so common, this is now the official language in the South), it is because of politics and propaganda that the bastard offspring (sadly born by rape) of a part of the old Empire claims that the true heirs of American greatness are but Mexicans—a scornful name that reduces the SUSA to only one of the many people that make it up—while a powerful chieftain in the North declares himself "President of the Holy United States".
After even this old relic of a state has fallen, a historian from the, uhm, Holy United States, decides to call them yet another name, "Managuans", after the site where New Washington was built. "Managuan Empire" has stuck, but helPost too long. Click here to view the full text.