It would be interesting to see how organizations of Pre Collapse America fare in this new environment. In the South, rural white communities might seek help from the remnants of the KKK who could form an orthodox theocratic entity. Maybe they eventually abandon the racism or possibly they become engaged in a race war with the descendants of Black Power movements which could be a descendant of the Black Panthers.Other entities could include descendants of National Guard divisions, paramilitary groups, Antifa, Nation of Islam and possibly even major gangs.
I've thought about the KKK, but due to the tenor of the times, I don't think I would get into it.With the MASSIVE success of the movie Black Panther, as well as the sports team based in Carolina, combined with the civil rights group, I could see a Black Panther order.
When it comes to orders like the Black Panthers, KKK etc. it must be remembered that they are not direct descendants of the groups like how the HRE isn't a direct descendant of Rome. Rather they are built upon memories of Old America which raises the interesting question of what the people think of the past.The arrivals of whites to America, American declaration of independence from Britain, the Civil War, World War I & II, Cold War and 9/11 could play huge roles in what Americans believe American mean.