Most authors that look at the subject have usually proposed 3+ groups post-balkanization. Tends to depend on whether it's simply an "After America" balkanizati

Most authors that look at the subject have usually proposed 3+ groups post-balkanization. Tends to depend on whether it's simply an "After America" balkanization or a complete apocalypse scenario. Table top roleplaying games are full of speculative fiction on those kinds of concepts. Nukes, or zombies, and sometimes black swan "magic" tend to be rather popular. After America would be like the Fall of the Roman Empire, or the collapse of the Chinese Jin (romance of the three kingdoms) and Tang (five dynasties, ten kingdoms) eras, usually because of human bickering over power and control. Occasionally, systems like Shadowrun have a "mild" apocalypse that mostly serves as a catalyst for balkanization. Whatever vestiges of a state remained fall apart under the stress. Complete apocalypse tends to be something like large scale devastation from a known threat that final gets used (nuclear, biological, dangerous machine sentience) and everybody's too busy dealing with their own issues to care about larger ideas like a continental federal state of "America." Either way, tends to result in 3+ most of the time. From looking at the Roman Empire and the multiple collapses of China though, it really does not take anything especially dramatic to result in pretty severe balkanization. Often its the old "Blue and the Grey" divide and then most of the West just does their own thing. Occasionally it's more like East Coast, Heartland, and often the West still is not really included. The result for the West has actually been one of the weirder parts of reading a lot of those settings. Often this undercurrent that the West has never really been a part of "America." The heavily populated East is still mostly fighting over the same issues with each other, the lightly populated West is just some far away land they occasionally pay attention to (mostly California and Texas).