1940s: The United States sends great numbers of soldiers to fight in World War II on the side of the Allies.

1970s: The United States fights the Vietnam War, an escalation of cold war tensions with the Soviet Union.

Today: As of 2005, the United States Army continues to fight in Iraq after having invaded the country based on the false claim that it was stockpiling weapons of mass destruction.

1940s: World War II finally lifts the United States out of the Great Depression (1929-39), and soldiers return home to start families in great numbers.

1970s: The Vietnam War ends, Richard Nixon resigns, the postwar economic prosperity in the United States dwindles due to energy crises and industrial competition from Asia.

Today: The United States economy remains strong despite the downturns following the September 11, 2001 terrorist attacks.

1940s: Tensions begin to show between Western capitalist countries...