On September 11, 2001, 19 al-Qaeda terrorists took control of four commercial aircraft and used them as suicide weapons in a series of four coordinated acts of terrorism to strike the World Trade Center in New York City, The Pentagon in Arlington County, Virginia, and an additional target in Washington, D.C. Two aircraft hit the World Trade Center while the third hit the Pentagon. A fourth plane did not arrive at its target, but crashed into a field in Pennsylvania after a passenger revolt. The intended target is believed to have been the United States Capitol. As a result, 2,977 victims were killed, making it the deadliest foreign attack on U.S. soil, exceeding Japan's surprise attack on Pearl Harbor in Honolulu, Hawaii, on December 7, 1941, which killed 2,335 members of the United States Armed Forces and 68 civilians. The effort was carefully planned by al-Qaeda, which sent 19 terrorists to take over Boeing 757 and Boeing 767 aircraft, operated by American Airlines and United Airlines.
Background
Al-Qaeda's origins date to 1979 when the Soviet Union invaded Afghanistan. Soon after the invasion, Osama bin Laden traveled to Afghanistan and helped organize Arab mujahideen. Together with Abdullah Azzam, a Palestinian-Jordanian who influenced bin Laden, they formed Maktab al-Khidamat (MAK) in 1984, to provide support for Arab mujahideen who came to join the jihad in Afghanistan.
Toward the end of the 1980s, the Soviets were retreating in defeat. Bin Laden and Azzam discussed the future of MAK and what to do with the mujahideen force that had built up. Bin Laden and Azzam both wanted to use the force as a "rapid reaction force" to defend oppressed Muslims around the world. Bin Laden wanted to train the mujahideen in terrorist tactics, but Azzam strongly disagreed with this approach, issuing a fatwa saying that it would violate Islamic law. Azzam reiterated the hadith that orders Muslims to kill no women or children.
In November 1989, soon after bin Laden and Azzam split, Azzam was killed in Peshawar, Pakistan. Azzam and his two sons were travelling to Jummah (Friday prayer) when a remote-control-activated bomb detonated, killing them. It is unknown for certain if bin Laden was behind this, but is thought unlikely. Nonetheless, bin Laden was then free to take full control of MAK, laying the groundwork for al-Qaeda. Under the guidance of Dr. Ayman al-Zawahiri, bin Laden became more radical.
In 1991, bin Laden moved to Sudan, where he led operations in East Africa, including the 1993 assault on U.S. troops at Mogadishu in Somalia. Under Saudi and American pressure, the Sudanese forced bin Laden out of Sudan in 1996, and he returned to Afghanistan.
Ideology
The Iraqi invasion of Kuwait in 1990 marked a point where bin Laden turned attention toward the United States. He urged the Saudi regime not to host the 500,000 U.S. soldiers, instead advocating use of a mujaheddin force to oust the Iraqis. Bin Laden strongly opposed the continued presence of the U.S. Armed Forces in Saudi Arabia. He interpreted the Prophet Muhammad as banning the "permanent presence of kafirun (infidels) in Arabia". This drove bin Laden to attack U.S. military targets in Saudi Arabia. The date chosen for the 1998 Kenyan embassy bombings (August 7), was eight years to the day that American troops were sent to Saudi Arabia.
Bin Laden also stated that he viewed the House of Saud (the Saudi royal family) as apostates. In Islam, the charge of apostasy is made against Muslims who become non-believers and reject Islam. Bin Laden also objected to U.S. alliances with the governments of Kuwait, Jordan, and Egypt. He viewed Israelis as kafirun who are unwelcome in "Muslim land". He objected to U.S. foreign policy in relation to Israel. He noted that key figures Madeleine Albright, Sandy Berger, and William Cohen, who were all Jewish, "drove Washington's undoubtedly pro-Israel policy" during the Clinton administration.