Freedom, I am more inclined to think the US is not really a nation in itself, but rather a collection of nations. Thus I think a civil war would spell doom for the US as a single entity. At the very least, I think there are three big nations of America (and possibly many more),
-“The North/Yankedom”: The Northeast + parts of the upper Midwest + the Pacific Northwest.
-“The South”: The former confederacy plus some Midwest states tacked on.
-The Southwest: a region in transition, with a large Hispanic population, but also a lot of white and black people who sometimes don’t like each other. This could end up being the most violent region in America if a civil war ever happens.
This is not to mention sub regions, like “Cascadia” or New England.
I am personally at a loss as to what might happen in places like New York state, which are highly diverse, but in the heart of traditional American power (the Northeast).