Remnants of North America: American Fracture

After the Day of 10,000 Suns, most of the American government fled south to the Panama Canal, however, two other factions emerged.

Orthodox US Government
The original US Government, which was in the second JFK cabinet, fled to the Panama Canal, with most officials in D.C. fleeing with him. They would, from the Panama Canal, take over the entirety of Panama, turning it into a pseudo-American colony. Though JFK would be assassinated shortly after leaving office in February 1969, the orthodox government stayed stable. To this day, they act as the legitimate American government, claiming all of America.

Miami Faction
Though most of the East Coast government fled to Panama, a small contingent accidentally landed in the ruins of Miami, which they initially thought was Panama. They would, from there, claim Miami. This contingent also had 2 dozen National Guard members, and were able to take over the nearly-annihilated city with little resistance. From Miami, they would take most of Florida, except for the Panhandle. They claim that the JFK cabinet abandoned America, since they fled to Panama, and claim that they are the real American Government.

Seattle Government
The Seattle Government, made up of most politicians outside of D.C. is the last of these factions, and also the weakest. In 1972, they declared that they were the official government of America, since they were unaware that the JFK cabinet survived. Canada also barely survived, keeping South British Columbia, South Alberta, and South Saskatchewan. Due to the direness of both Canada and Seattle's situation, they reluctantly united, forming the Canadian-American Unity Government. With this, they now spanned from Vancouver to Bismarck, which was their furthest point.

The Fourth Possibility
It is constantly possible that the Union of Southwestern States will declare legitimacy, and since they have massively and excellently rebuilt since the Day, it is a massive risk for the Seattle Government. It is also a risk for the San Francisco Commonwealth, the Soviet refugees. In fact, the SFC is constantly on the verge of declaring legitimacy as well, since most of the Old World is no longer habitable.

Dixie
Most of the American South is currently barely habited, and is constantly fought for by the Seattle Government from Missouri, the USS from Louisiana, Oklahoma, and Texas, and the Miami Government from Florida. Multiple attempts have been made by Wastelanders to establish a government in Dixie, although these usually fail.

The Midwest
The Midwest is home to one faction, which is the Chicago United Corporations. The CUC is made up of businesses from Pre-Day America, but have almost no contact with the outside world. They currently control Chicago, small chunks of north Illinois, and Gary, Indiana.

List of American/possible American Governments
Orthodox Panama Government
Miami Government
Canadian-American Unity Government
Union of Southwestern States
Commonwealth of San Francisco
Dixie Wastelanders
Chicago United Corporations

Mexico
After the Day, Mexico was completely devastated. The central government collapsed within days, and led to a 7-way civil war within Mexico.
The Day In Mexico
The Day in Mexico only hit a few major cities, Mexico City, Tijuana, Monterrey, Guadalajara, and Juarez. Despite this, the nation collapsed completely, with many rebel groups seizing their opportunity, which lead to an early Guadalajara Cartel. The main of these rebel groups, the Zapatistas, seized most of rural South Mexico, while the cartels fled to the North, barely holding onto Guadalajara.