September 11 attacks


The September 11 attacks, colloquially known as 9/11, were four coordinated Islamist terrorist suicide attacks by al-Qaeda against the United States in 2001. Nineteen terrorists hijacked four airliners, then flew one into each of the Twin Towers at the World Trade Center in New York City, and another into the Pentagon, the headquarters of the U.S. Department of Defense, in Arlington County, Virginia. The fourth plane crashed in a rural Pennsylvania field during a passenger revolt. In response to the attacks, the United States launched the global war on terror over two decades, with the mission to eliminate hostile groups deemed terrorist organizations, and the governments purported to support them.
Ringleader Mohamed Atta flew American Airlines Flight 11 into the North Tower of the World Trade Center complex at 8:46 a.m. At 9:03 a.m., hijacker Marwan al-Shehhi flew United Airlines Flight 175 into the South Tower. Both collapsed within an hour and forty-two minutes, destroying the remaining five structures in the complex. Hijacker Hani Hanjour flew American Airlines Flight 77 into the Pentagon at 9:37 a.m., causing a partial collapse. United Airlines Flight 93, flown by hijacker Ziad Jarrah, was believed to target either the United States Capitol or the White House. Alerted to the previous attacks, the passengers revolted and the hijackers crashed the aircraft into a field near Shanksville, Pennsylvania, at 10:03 a.m. The Federal Aviation Administration ordered a ground stop for all traffic in U.S. airspace, requiring all airborne aircraft to return to their point of origin or divert to Canada. The actions undertaken in Canada to support incoming aircraft and their occupants were collectively titled Operation Yellow Ribbon.
That evening, the Central Intelligence Agency informed President George W. Bush that its Counterterrorism Center had identified the attacks as having been the work of al-Qaeda under Osama bin Laden. The United States responded by launching the war on terror and invading Afghanistan. NATO's invocation of Article 5 of the North Atlantic Treaty—its only usage to date—called upon allies to fight al-Qaeda. As U.S. and allied invasion forces swept through Afghanistan, bin Laden eluded them. He denied any involvement until 2004, when excerpts of a taped statement in which he accepted responsibility for the attacks were released. Al-Qaeda's cited motivations included U.S. support of Israel, the presence of U.S. military bases in Saudi Arabia and sanctions against Iraq. The nearly decade-long manhunt for bin Laden concluded in May 2011, when he was killed during a U.S. military raid in Abbottabad, Pakistan. The war in Afghanistan continued for another eight years.
The attacks killed 2,977 people, injured thousands more, and gave rise to long-term health consequences while causing at least billion in infrastructure and property damage. It remains the deadliest terrorist attack in history, as well as the deadliest incident for firefighters and law enforcement personnel in American history, killing 343 and 72 members, respectively. The crashes of Flight 11 and Flight 175 were the deadliest aviation disasters of all time, and the collision of Flight 77 with the Pentagon resulted in the fourth-highest number of ground fatalities in a plane crash in history. The destruction of the World Trade Center and its environs seriously harmed the U.S. economy and induced global market shocks. Many other countries strengthened anti-terrorism legislation and expanded their powers of law enforcement and intelligence agencies. The total number of deaths caused by the attacks, combined with the death tolls from the conflicts they directly incited, has been estimated by the Costs of War Project to be over 4.5 million.
Cleanup of the World Trade Center site was completed in May 2002, while the Pentagon was repaired within a year. After delays in the design of a replacement complex, six new buildings were planned to replace the lost towers, along with a museum and memorial dedicated to those who were killed or injured in the attacks. The tallest building, One World Trade Center, began construction in 2006, opening in 2014. Memorials to the attacks include the National September 11 Memorial & Museum in New York City, the Pentagon Memorial in Arlington County, Virginia, and the Flight 93 National Memorial at the Pennsylvania crash site.

Background

In 1996, Osama bin Laden of the Islamist militant organization al-Qaeda issued his first Fatwa|, which declared war against the United States and demanded the expulsion of all American soldiers from the Arabian Peninsula. In a second 1998, bin Laden outlined his objections to American foreign policy with respect to Israel, as well as the continued presence of American troops in Saudi Arabia after the Gulf War. Bin Laden maintained that Muslims are obliged to attack American targets until the aggressive policies of the U.S. against Muslims were reversed.
Bin Laden asserted that all Muslims must wage a defensive war against the United States and combat American aggression. He further argued that military strikes against American assets would send a message to the American people, attempting to force the U.S. to re-evaluate its support to Israel, and other aggressive policies. In a 1998 interview with American journalist John Miller, bin Laden stated:

Osama bin Laden

in the years prior to 1996, when the Sudanese government exiled him after Saudi Arabia and the U.S. had pressured them. Bin Laden returned to Afghanistan, which, by then, was ran by the Taliban. They allowed al-Qaeda to use the country as its base of operations.
Bin Laden orchestrated the September 11 attacks. He initially denied involvement, but later recanted his denial. Al Jazeera broadcast a statement by him on September 16, 2001: "I stress that I have not carried out this act, which appears to have been carried out by individuals with their own motivation". In November 2001, U.S. forces recovered a videotape in which bin Laden, talking to Khaled al-Harbi, admitted foreknowledge of the attacks. On December 27, a second video of bin Laden was released in which he, stopping short of admitting responsibility for the attacks, said:
Shortly before the 2004 U.S. presidential election, bin Laden used a taped statement to publicly acknowledge al-Qaeda's involvement in the attacks. He admitted his direct link to the attacks and said they were carried out because:
Bin Laden personally directed his followers to attack the World Trade Center and the Pentagon. Another video obtained by Al Jazeera in September 2006 showed bin Laden with one of the attacks' chief planners, Ramzi bin al-Shibh, as well as hijackers, Hamza al-Ghamdi and Wail al-Shehri, amidst making preparations for the attacks.

Khalid Sheikh Mohammed and other al-Qaeda members

Journalist Yosri Fouda of the Arabic television channel Al Jazeera reported that in April 2002, al-Qaeda member Khalid Sheikh Mohammed admitted his involvement in the attacks, along with Ramzi bin al-Shibh. The 2004 9/11 Commission Report determined that the animosity which Mohammed, the principal architect of the 9/11 attacks, felt towards the United States had stemmed from his "violent disagreement with U.S. foreign policy favoring Israel".9/11 Commission Report, p. 147. Mohammed was also an adviser and financier of the 1993 World Trade Center bombing and the uncle of Ramzi Yousef, the lead bomber in that attack. In late 1994, Mohammed and Yousef moved on to plan a new terrorist attack called the Bojinka plot planned for January 1995. Despite a failure and Yousef's capture by U.S. forces the following month, the Bojinka plot would influence the later 9/11 attacks.

Motives

Osama bin Laden's declaration of holy war against the U.S. in his 1996, and similar statements that called for the killing of Americans, are seen by investigators as evidence of his motivation for the attacks. In November 2001, bin Laden defended the attacks as retaliatory strikes against American atrocities against Muslims across the world. He also maintained that the attacks were not directed against women and children, asserting that the targets of the strikes were symbols of America's "economic and military power".
In bin Laden's November 2002 Letter to the American People, he identified al-Qaeda's motives for the attacks:
After the attacks, bin Laden and Ayman al-Zawahiri released additional recordings, some of which repeated the above reasons. Two relevant publications were bin Laden's 2002 letter and 2004 videotape.
As an adherent of Islam, bin Laden believed that non-Muslims are forbidden from having a permanent presence in the Arabian Peninsula. He thus considered the U.S. troop presence a provocation to all Muslims. In 1996, bin Laden issued a calling for the troops to leave. One analysis of suicide terrorism suggested that without U.S. troops in Saudi Arabia, al-Qaeda likely would not have been able to get people to commit to suicide missions. In the 1998, al-Qaeda identified the Iraq sanctions as a reason to kill Americans, condemning the "protracted blockade" among other actions that constitute a declaration of war against "Allah, his messenger, and Muslims".
In 2004, bin Laden claimed that the idea of destroying the towers had first occurred to him in 1982 when he witnessed Israel's bombardment of high-rise apartment buildings during the 1982 Lebanon War. Some analysts, including political scientists John Mearsheimer and Stephen Walt, also claimed that U.S. support of Israel was a motive for the attacks. In 2004 and 2010, bin Laden again connected the September 11 attacks with U.S. support of Israel, although most of the letters expressed bin Laden's disdain for President Bush and bin Laden's hope to "destroy and bankrupt" the U.S.
Other motives have been suggested in addition to those stated by bin Laden and al-Qaeda. Some authors suggested the "humiliation" that resulted from the Islamic world falling behind the Western world—this discrepancy was rendered especially visible by globalization—as well as a desire to provoke the U.S. into a broader war against the Islamic world in the hope of motivating more allies to support al-Qaeda. Similarly, others have argued the 9/11 attacks were a strategic move to provoke America into a war that would incite a pan-Islamic revolution.