Reagan: Focused on military buildup and confronting the Soviet Union. Gorbachev: Sought to reform the Soviet Union and improve relations with the US through Glasnost and Perestroika.

Persian Gulf War: Decisive victory with limited casualties. Vietnam War: Protracted conflict with high casualties and political division.

Yeltsin: Focused on establishing democracy and a free market economy, but struggled with corruption. Putin: Consolidated power and oversaw a period of economic growth, but with concerns about authoritarianism.

Tiananmen Square: Limited direct intervention. Kosovo: Military intervention through NATO to stop ethnic cleansing.

Start: Ideological differences, Soviet expansionism. End: Soviet economic problems, Gorbachev's reforms, Reagan's pressure.

Desert Shield: Defensive buildup to deter further Iraqi aggression. Desert Storm: Offensive military operation to liberate Kuwait.

Yugoslavia: US intervened to stop ethnic cleansing. Rwandan genocide: US did not intervene.

Glasnost: Increased political openness and freedom of expression. Perestroika: Restructuring of the Soviet economy with some free-market practices.

Sandinistas: Overthrew the authoritarian regime and implemented leftist policies. Contras: Exiles fighting against the Sandinistas to disrupt the economy.

INF Treaty: Removed and destroyed intermediate-range missiles in Europe. SALT Treaties: Aimed to limit the growth of nuclear arsenals.

Gorbachev's policy of political openness to end political repression and move toward greater political freedom for Soviet citizens.

Gorbachev's policy of restructuring the Soviet economy by introducing some free-market practices.

An antimissile system using lasers and particle beams to destroy incoming missiles in space; dubbed 'Star Wars'.

Exiles fighting against the Sandinistas in Nicaragua, based in Honduras and Costa Rica, and supported by the CIA.

A sudden, violent, and illegal seizure of power from a government.

The initial US troop buildup in Saudi Arabia to deter Saddam Hussein from advancing beyond Kuwait.

The military operation to liberate Kuwait from Iraqi occupation in 1991.

The systematic forced removal of ethnic or religious groups from a given territory.

A scandal involving the Reagan administration's secret sale of arms to Iran in exchange for the release of American hostages and the use of the profits to illegally fund the Contras in Nicaragua.

An agreement between the US and the Soviet Union in 1987 to remove and destroy all intermediate-range missiles in Europe.

Cause: Reagan wanted to restore US military might and intensify Cold War competition. Effect: Increased military spending, development of new weapons systems like SDI ('Star Wars').

Cause: Desire to free American hostages in Lebanon and illegally fund the Contras. Effect: Illegal arms sales, constitutional crisis, damaged Reagan administration.

Cause: Declining Soviet economy and need for reform. Effect: Political openness, economic restructuring, ultimately contributing to the breakup of the Soviet Union.

Cause: Pro-democracy movement in China. Effect: Government crackdown, ending the brief period of political openness.

Cause: Iraq's desire to control Kuwait's oil reserves. Effect: The Persian Gulf War, US intervention, and the liberation of Kuwait.

Cause: Milosevic ended Kosovo’s autonomy within Yugoslavia and imposed Serbian rule. Effect: NATO aerial assault in 1999, ethnic cleansing.

Cause: Economic problems in the Soviet Union, Gorbachev's reforms, Reagan's pressure. Effect: Dissolution of the Soviet Union, end of the bipolar world order.

Cause: Iraq's invasion of Kuwait and threat to oil supplies. Effect: Liberation of Kuwait, high approval ratings for Bush, but Saddam Hussein remained in power.

Cause: Al Qaeda's anti-American sentiment and desire to harm US interests. Effect: US air strikes on Al Qaeda training camps in Afghanistan and Sudan.

Cause: Clinton controversially did not intervene during the 1996 Rwandan genocide. Effect: ethnic cleansing.