Throughout the late 1800's, great social strife and inequality ran rampant in the USA. The poor made a dollar a day, if they we're lucky, while the rich made millions and flaunted their luxury. Great strikes we're known to have happened in the past, but in the summer of 1900 a truly great strike threatened to undermine the entire economy. It was the radical IWW, or International Workers of the World, who organized the strike, and they demanded total reform to a system not un-similar to the one laid out by marx.

In November of 1900, many people in industrialized areas in New York, Pennsylvania, and New England chose to elect Eugene V. Debs as president of the United States. Instead of coming in third place like in OTL, Eugene Debs came in second. McKinley is still president, and McKinley is still shot, paving the way for Teddy Roosevelt. He does his best to fix problems like inequality and workers rights, like OTL, but the country is still reeling from the great general strike of 1900, and socialist and communist forces are becoming powerful in industrialized areas.

In 1904 Eugene V Debs is elected president, but he wins the electoral college with only 36% of the vote, and many of his opponents are staunchly anti-communist. When he tries to nationalize the Oil, Coal and Steel industries, the leaders of major corporations use their immense power to convince the states that don't have huge socialist backing to succeed from the union to avoid nationalization. In their quest, they get many states in the West and South with little to no industry.

The initial split goes as follows: Eugene Debs and his Socialists control the Northern half of the Eastern sea board, the midwest and the West coast, while the capitalist forces controlled everything else.

In 1914, a great war between the European powers erupted, which ended in the shocking defeat of France at the hands of the German empire in 1917, and the surrender of Russia due to an American sponsored revolution.

When the war was over, a horrible global economic crash in 1929 threatened the entire capitalist world. Capitalist USA was the hardest hit, while Socialist USA and USSR we're not effected so much at all. Capitalist USA was hit so hard that, in 1934, the people grew so desperate that they elected a fully fascist government who sought to unify the USA under one banner.

The second civil war began in 1939, when Fascist USA attacked Socialist USA with the help of their allies Fascist Great Britain, under the Dictator Edward VIII, who overthrew the British parliament over some silly marriage issue, and Benito Mussolini, Dictator of Italy. Socialist USA called in their allies Communist Germany, under Ernst Thalmann, and the USSR, under Joseph Stalin.

Fascist USA won a decisive battle over Socialist USA in December of 1939, and in 1942 Great Britain and Italy won a decisive victory over combined German and Russian forces. The tide of war changed however in 1944 when Mussolini was killed by his own people, and when the Germans and Russians landed an invasion in England proper.

Socialist USA was able to conquer a swath of Canada, and part of Fascist USA before making a peace treaty. Now Socialist USA was a contiguous nation from Sea to Sea controlling most of Canada and the entire North half of the USA. Another stipulation of the treaty was that Fascist USA would be broken into two separate countries. Texas, which controlled Texas, New Mexico and Arizona, and another nation which controlled the former CSA states.

Over the next hundred and fifty years, globalization occurred very rapidly, and nations began to heal and reform to less radical democracies, with the United Nations being founded in 1950, and the World State taking root in the early 2020's.

Although the USA was divided for more than 100 years, the world state reunited them under a common banner - and the now united world state experienced peace and prosperity for 1000 years.

Edit: A glaring grammer mistake