The Second American Civil War was an event taking place from 2051 to 2054. Its end resulted in the collapse of the United States of America.
A number of factors went into starting the 2ACW - including increased tribalism between the left and the right (accelerated by Trump's re-election in 2020). As well as being battered by numerous recessions during and since the Trump presidency.
Treaty of Paris
The Treaty of Paris was signed by all parties on July 4th, 2054 - officially ending the war. It resulted in the dissolution of the USA as well as the independence of California, the United States of the Rockies, New England, Union of the Great Lakes, Cascadia, Texas, Florida (including Puerto Rico and the Virgin Islands), the Great Plains Federation, Columbia, Hawaii, and the Republic of New York. Canada annexes Alaska, while the Oceanian Federation annexes Guam, the Northern Marianas, and other former American Pacific territory).
The 2ACW resulted in disunity in the Americas for the first time, as well as starting the "Second Great Depression".
Some of the Americans, those who took part in the "American Exodus" (occuring from 2021-2025, as a result of anger over Trumpian policies, migrating to Canada and other neighboring countries), returned back to the American heartland. Though a majority stayed in their new residence.