What Happened on September 11, 2001: The Attacks and Their Legacy

On the morning of Tuesday, September 11, 2001, nineteen hijackers took control of four commercial airliners and used them as weapons against the United States. Two planes struck the twin towers of the World Trade Center in New York, one struck the Pentagon outside Washington, and the fourth crashed in a field near Shanksville, Pennsylvania, after its passengers and crew fought back. The attacks killed 2,977 people from 90 countries. What happened on September 11, 2001, still shapes how Americans travel, how the government gathers intelligence and how the country remembers.

What Happened on September 11, 2001: The Morning Timeline

All four flights were bound for California. Three took off from Boston and Washington Dulles between 7:59 and 8:20 a.m.; the fourth was held up by heavy morning traffic at Newark. The 9/11 Commission later reconstructed the morning minute by minute. All times below are Eastern.

Time	Event
7:59 a.m.	American Airlines Flight 11 departs Boston for Los Angeles
8:14 a.m.	United Airlines Flight 175 departs Boston for Los Angeles
8:20 a.m.	American Airlines Flight 77 departs Washington Dulles for Los Angeles
8:42 a.m.	United Airlines Flight 93 departs Newark for San Francisco
8:46 a.m.	Flight 11 strikes the North Tower of the World Trade Center
9:03 a.m.	Flight 175 strikes the South Tower
9:37 a.m.	Flight 77 strikes the west side of the Pentagon
9:42 a.m.	The FAA orders every aircraft in US airspace to land
9:59 a.m.	The South Tower collapses
10:03 a.m.	Flight 93 crashes near Shanksville, Pennsylvania
10:28 a.m.	The North Tower collapses

Between 16,400 and 18,000 people were in the World Trade Center complex when the first plane hit, according to the National September 11 Memorial & Museum. The 9/11 Commission found that all but about 100 of the thousands of civilians working below the impact zones escaped, often with help from firefighters, police officers and other responders who climbed into the towers as workers came down.

The nationwide order to land had never been given before. About 4,500 commercial and private aircraft came down at the nearest available airports, many of them far from where their passengers had planned to go.

The People Who Were Lost

The 2,977 victims included office workers, restaurant staff, visitors, airline passengers and crew members, military personnel and civilian employees at the Pentagon, and hundreds of rescuers. The Memorial & Museum counts 2,753 deaths in New York, 184 at the Pentagon and 40 aboard Flight 93.

The Fire Department of New York lost 343 members, the New York City Police Department lost 23 officers and the Port Authority Police Department lost 37. Many of them died while helping others get out of the towers.

Flight 93 holds a distinct place in the story. Its departure ran more than 25 minutes late, so by the time hijackers seized it, people on board could learn by phone what had already happened in New York. At least ten passengers and two crew members made calls, and several described a plan to retake the plane. Their assault on the cockpit began at 9:57 a.m. The 9/11 Commission concluded that the hijackers had aimed the plane at the Capitol or the White House; it never reached Washington.

Rescue, Recovery and the Weeks That Followed

The search at the World Trade Center site, soon called Ground Zero, became a recovery operation that lasted more than eight months. Workers removed about 1.8 million tons of debris, and the effort officially ended on May 30, 2002, when the last column of steel was carried out.

Much of the country paused. Civilian air traffic was halted nationwide, and the New York Stock Exchange did not reopen until September 17. Major League Baseball suspended its schedule for a week, which pushed that fall’s World Series into November for the first time. On September 21, a televised benefit called “America: A Tribute to Heroes” raised more than $200 million for victims and their families.

Washington moved quickly as well. On October 7, American and British forces began airstrikes in Afghanistan against al-Qaeda, the group behind the attacks, and the Taliban government that sheltered it. On October 26, President George W. Bush signed the USA PATRIOT Act, which expanded surveillance and information-sharing powers. On November 19, the Aviation and Transportation Security Act created the Transportation Security Administration, putting airport screening under federal control.

How 9/11 Changed American Security

Several of the most visible changes in daily life trace back to that morning. Airport screening became a federal job under the new TSA. In November 2002, Congress created the Department of Homeland Security, which brought all or part of 22 federal departments and agencies into a single Cabinet department; that story continues on the 2002 calendar page.

The independent 9/11 Commission released its final report on July 22, 2004. It found “failures of imagination, policy, capabilities, and management” across the government and recommended a National Counterterrorism Center and a single national intelligence director to oversee the intelligence agencies. Congress wrote both into the Intelligence Reform and Terrorism Prevention Act, which President Bush signed on December 17, 2004.

Remembering September 11 Today

Congress made September 11 a national day of remembrance in a law signed on December 18, 2001. Patriot Day is not a federal holiday, but presidential proclamations ask Americans to fly flags at half-staff and to observe a moment of silence beginning at 8:46 a.m. Eastern time, when the first plane struck.

Three memorials mark the sites. The National September 11 Memorial in New York, with twin reflecting pools in the footprints of the towers, opened in September 2011, and its museum opened to the public on May 21, 2014. The Pentagon Memorial honors the 184 people killed there. The Flight 93 National Memorial near Shanksville includes the Tower of Voices, which holds 40 wind chimes, one for each passenger and crew member.

The health effects are still unfolding. More than 400,000 people are estimated to have been exposed to the dust and smoke in Lower Manhattan, and more than 80,000 are known to have 9/11-related illnesses. The World Trade Center Health Program, created by the James Zadroga 9/11 Health and Compensation Act of 2010, serves more than 145,000 responders and survivors and is authorized until 2090. The September 11th Victim Compensation Fund, reopened under the same law, can accept claims until October 1, 2090.

Many readers come to this date through family stories. If you are tracing where someone was that week, the full 2001 calendar shows how the attacks fell in the school and work year, and our guide to what happened on the day you were born explains how to research a specific date.