1980s-1990s: Iran and Iraq engage in war between 1980 and 1988. After this war ends, Iraq invades Kuwait in 1990. The United States eventually engages in war with Iraq on behalf of Kuwait.

Today: Although the United States defeated Iraq in the Gulf War, Sadam Hussein is still in power. American troops are still stationed in the Middle East and an uneasy peace prevails.

1980s: During this decade, the unthinkable happens: the Soviet Union crumbles and the Eastern European Communist bloc falls apart. Yugoslav President Tito's death in 1980 sets up the devolution of his country.

Today: The breakup of Yugoslavia leads to a confusing war and ethnic cleansing in Bosnia, Serbia, Croatia, and Kosovo in the closing years of the 1990s. The United States participates in United Nations peacekeeping missions and continues to station troops in the troubled area in the following decades.

1980s: At the...