11 September 2001: How the attacks changed the world

11 September 2001: How the attacks changed the world
Clean-up and rescue work continues at the Pentagon, 13 September 2001 after the 11 September terror attack.
Reuters

The attacks of 11 September 2001 killed 2,977 people and reshaped U.S. national security and foreign policy. Nineteen terrorists associated with al-Qaeda hijacked four commercial aircraft in a coordinated operation in New York, Virginia and Pennsylvania.

The attacks led to a U.S.-led military campaign in Afghanistan, new counter-terrorism measures and major changes to intelligence and homeland security.

What happened on 11 September?

On the morning of 11 September 2001, 19 terrorists associated with al-Qaeda hijacked four commercial aircraft travelling from the U.S. East Coast to California.

At 8:46 a.m., American Airlines Flight 11 struck the North Tower of the World Trade Centre in New York. 

At 9:03 a.m., United Airlines Flight 175 hit the South Tower, making clear that the first crash had been part of a coordinated attack.

The World Trade Centre's South Tower burns after being struck by United Airlines Flight 175 in New York City, 11 September 2001.
Reuters

At 9:05 a.m., President George W. Bush was informed of the second impact while visiting a school in Florida.

At 9:25 a.m., the Federal Aviation Administration ordered a nationwide ground stop, preventing further aircraft from taking off.

At 9:37 a.m., American Airlines Flight 77 crashed into the Pentagon, the headquarters of the U.S. Department of Defense, in Arlington, Virginia. Five minutes later, the FAA ordered all aircraft already in U.S. airspace to land as soon as possible.

Clean-up and rescue work continues at the Pentagon, 13 September 2001, after the 11 September terror attack.
Reuters

At 9:59 a.m., the South Tower collapsed, less than an hour after it was hit. Four minutes later, United Airlines Flight 93 crashed in Somerset County, Pennsylvania. 

The 9/11 Commission found that passengers and crew had attempted to overcome the hijackers after learning what had happened in New York.

At 10:28 a.m., the North Tower collapsed, 102 minutes after the first impact.

In total, 2,977 people were killed at the World Trade Centre, the Pentagon and in Pennsylvania

Firefighters walk amid rubble near the base of the destroyed World Trade Centre south tower in New York, 11 September 2001.
Reuters
Who carried out the attacks?

The 9/11 Commission concluded that the attacks were driven by Osama bin Laden and al-Qaeda.

Bin Laden had become involved with militants who travelled to Afghanistan during the war against the Soviet Union and later became the leader of al Qaeda.

The group had already carried out attacks against U.S. targets, including the 1998 bombings of U.S. embassies in Kenya and Tanzania and the 2000 attack on the USS Cole in Yemen.

The 9/11 Commission documented bin Laden's opposition to the presence of U.S. forces in Saudi Arabia and his broader opposition to U.S. policy in the Middle East.

In 1996, he issued a declaration of jihad against U.S. forces in Saudi Arabia. In 1998, bin Laden and other al Qaeda leaders issued a statement calling for attacks against Americans.

Osama bin Laden speaks to a journalist, 10 November 2001.
Reuters

The commission found that bin Laden's priority was to launch a major attack directly against the United States. It also documented his view that attacks against the U.S. could support the insurgency in the Israeli-occupied territories and protest the presence of U.S. forces in Saudi Arabia. U.S. response

On 20 September 2001, President George W. Bush addressed a joint session of Congress and demanded that the Taliban hand over bin Laden and other al Qaeda leaders.

Former U.S. President George W. Bush speaks during an event commemorating the 20th anniversary of the 11 September 2001 attacks, U.S., 11 September 2021.
Reuters

The 9/11 Commission said the Taliban regime had provided a sanctuary for al-Qaeda and that the U.S. government had repeatedly tried to persuade the Taliban to expel bin Laden before the attacks.

The United States and its coalition partners began a military campaign in Afghanistan on 7 October 2001, targeting terrorist facilities and Taliban military and political assets, according to the U.S. State Department's Office of the Historian. Kabul fell on 13 November.

The Taliban was removed from power, but the conflict continued

The war in Afghanistan

The campaign developed into a longer war involving U.S., NATO and Afghan government forces against the Taliban and other militant groups.

The United States remained involved in Afghanistan for almost two decades. In February 2020, Washington and the Taliban signed an agreement covering the withdrawal of U.S. and other foreign forces.

The Taliban returned to power in August 2021 as U.S. and allied forces completed their withdrawal.

The attacks led to major changes in U.S. security policy. The FBI calls its investigation the largest in the Bureau's history, while terrorism became a central national-security priority.

Congress passed the USA PATRIOT Act in October 2001, expanding intelligence and law-enforcement powers. The U.S. government also introduced new aviation and homeland-security measures, including the creation of the Department of Homeland Security.

Osama bin Laden remained a target of U.S. intelligence agencies for almost a decade.

In May 2011, U.S. forces raided a compound in Abbottabad, Pakistan, where bin Laden was living. He was killed during the operation.

A model of the compound in Abbottabad, Pakistan, where Osama bin Laden was killed is displayed at the 9/11 Museum in New York, U.S., 7 November 2019.
Reuters
Reuters
The legacy of 11 September

The attacks led to major changes in U.S. policy towards terrorism and national security, including the military campaign in Afghanistan, new homeland-security structures and expanded intelligence and law-enforcement powers.

Twenty-five years later, 11 September remains a defining event in modern U.S. history, with lasting effects on security policy and international relations.

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