Riven by generations of war, Afghanistan became a haven for lawless terrorist groups like al-Qaida.

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1988 -- al-Qaida's Foundation

In 1979, the government of Afghanistan requests military intervention from the Soviet Union, in hopes of quelling Afghani rebels. At about the same time, Osama bin Laden, a member of a wealthy family from Saudi Arabia, leaves college to help Afghani rebels fight the invading Soviet Union. The rebels succeed in driving out the Soviets, and bin Laden returns to Saudi Arabia, energized by the victory. In 1988 or 1989, he forms a group called al-Qaida (in Arabic, "The Foundation") dedicated to driving Western influences and military forces out of the Middle East and to opposing the United States' support of Israel.

Bin Laden sets about creating strategies to achieve his goals, including tactics such as violence against civilians and suicide bombings. In 1993, al-Qaida-sponsored attacks kill 18 American soldiers in Somalia; in the same year, his group aids in a car bomb attack on the World Trade Center. The organization also claims responsibility for killing hundreds of other people in the U.S. embassies in Kenya and Tanzania in 1998.