In 1944, the Soviet Union developed the first nuclear bomb. They quickly used it on Berlin, killing Hitler and ending the war in Europe. The Allies placed a permanent occupation force in France and Italy, pushing them towards the far Left. The Soviets captured German military secrets. Creating nuclear missiles and putting a man in space in 1947. The Soviets occupied China and Korea and the Allies were forced to initiate Operation Downfall (the Allied invasion of Japan) in 1947. Most of Japan's adult population was killed and the Soviets were installed as an occupation force by the UN.
Between 1948 and 1972, many nations turned to socialism. France, Italy and West Germany joined the Warsaw Pact. And Britain and Spain developed popular communist movements. Vietnam, Laos, Cambodia and India became Communist. Iran was ruled by a socialist government and Egypt tilted towards the Left. Much of Latin America turned communist and America was forced to accept Soviet terms during the Cuban Missile Crisis. America did not have the political weight, massive armies and high-tech weaponry of the communists.
In 1973, the UN was dissolved and the nations split into the United Socialist League (USL), led by the USSR, and the League of Democratic States (LDS), led by the USA. The LDS had little power and the "Cold War" was just the waning of America's power.
In 1982, Great Britain and Spain, the only major democratic powers besides America, were engulfed in military coups. the democratic governments were removed and socialist governments took their place. The LDS was dissolved. America was the only nation left to stand up to the communists.
In 1984, Operation Red Storm was launched by the USL. Troops poured into Alaska, California and the Atlantic Seaboard. Cuba landed troops in Florida and the Latin states marched into Texas. The United States turned into a much smaller, communist country in a matter of weeks. The USL quickly subdued the other democratic states shortly afterwards.
What had seemed impossible during the dark days of WW2 had come true.
Socialism had triumphed!