Century of pain

The Century of Pain was an era of American History spanning from 2093 to 2216 (123 years) where the United States underwent an extended period of civil, economic, social and political upheaval and eventual collapse. Most historians consider the start of the century with the Inauguration of President Quinton Kaminski. His economic policies dragged the United State into a depression with long lasting effects. His successor, William Rowell only lasted two months in office as his social policies, open embrace of fascism and use of a private army to conduct terror campaigns across the country lead to his forced removal during the White House Siege. The Administration of Theodore Riddley while considered one of the best in American history, oversaw the start of World War Four and the return of George Washington. 
In 2110 the planet would be burned and Eleven Billion killed during Doomsday. The ensuing chaos and death destroyed the world order and civilization as a whole. The election of Benjamin Atwood to the Presidency had the lowest turnout for any election in history and his four year authoritarian regime saw thousands dead as he tore through the North American continent reunifying the United States by brutal force. With the exception of Garret Columbia the next two Administrations of James Capone and Wolfgang Stanaway saw the President become something of a mob boss with little regard for the law. Mason Dillinger and Phillip Kerr saw an massive improvement of the standard of living in the United States but all of the progress of the two eight year administrations would be undone by Ferdinand Vu who's Socialist and Trotskyist policies brought the United States into a third depression.
This would see the election of Otto Cromwell who's founding of the Imperialist Party accidentally laid the ground work for it's slow takeover of the American Government. The Administrations of Florentino Archuleta, Roscoe Pasquale, Barron Dietrich, Minh Arias and Mohammed Dockery saw the Imperialist Party slowly take control of the American Government transforming the Nation into a one party regime with sham elections. This would culminate with the passage of the 33rd Amendment to the Constitution that finally dropped the façade of free elections and gave the power to choose the President over to the Imperialist Party Council. This saw the Confirmation of Thorton Echevarria as President. After eight years in office his third term in 2200 saw the final culmination of decades of Imperialist rule when he, with the Declaration of the New Order created an American Empire with himself as Emperor.
This would near right away mark the start of the Third American Civil War as Iraq was the first state to secede from the Union. Fighting would rage on for a decade until an underground resistance group called the Commawatch was formed to actively overthrow the Imperialist Party and restore the United States. This sparked the start of the Second American Revolutionary War. By March, 2215 most of the US had broken up, Congress had dissolved and a plot was hatched to assassinate Emperor Echevarria. This plan worked and Echevarria was killed by his Vice President Barnabas Blankenship on March 15, 2215. The next year saw the rapid collapse of the Imperialist Party as control of the Federal Government was snatched from them and their forces obliterated. On June 1, 2216 Imperialist General Henry McCormack officially surrendered his remaining forces after an eleven day siege of his bunker. President Blankenship declared that the "war was over, the revolution had won, and America lived".
This is the point where most consider the century of pain as having ended as while issues with reconstruction were paramount and ongoing there was an end to the shocking pain and horrors seen during the past 123 years.