By: HISTORY.com Editors
September 11 Attacks
The Manhattan skyline following the terrorist attacks on the World Trade Center.
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World Trade Center
2
Osama bin Laden
3
Where Did the 9/11 Planes Take Off From?
4
Pentagon Attack
5
Twin Towers Collapse
6
Flight 93
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How Many People Died in the 9/11 Attacks?
8
America Responds to the Attacks
9
Department of Homeland Security Is Created
10
Economic Impact of 9/11
11
Victim Compensation Fund
12
Anniversary and Memorial
13
Photo Galleries
14
Sources
On September 11, 2001, 19 terrorists from the Islamic extremist group al Qaeda—founded by Osama bin Laden—hijacked four commercial passenger airplanes and carried out coordinated suicide attacks against targets in the United States. Two of the planes were flown into the twin towers of the World Trade Center in New York City. Within two hours, both towers had collapsed into rubble, demolishing a large section of lower Manhattan. A third plane hit the Pentagon in Arlington, Virginia, just outside Washington, D.C. The passengers and crew of the fourth plane fought back, and the hijackers crashed the plane in a field near Shanksville, Pennsylvania.
Almost 3,000 people were killed in the 9/11 terrorist attacks, including the 19 al Qaeda terrorists. The shocking events of September 11 were televised globally and left much of the world reeling in horror. The administration of President George W. Bush responded by declaring a “war on terror” and launching the U.S.-led invasion of Afghanistan. The attacks also led to a sweeping reorganization of the federal government, including the creation of the Department of Homeland Security.
9/11 Timeline
A timeline of the events on September 11, 2001.
World Trade Center
On September 11, 2001, at 8:46 a.m. on a clear Tuesday morning, American Airlines Flight 11, a Boeing 767 carrying thousands of gallons of jet fuel, crashed into the North Tower of the World Trade Center in New York City.
The impact left a gaping, burning hole between the 93rd and 99th floors of the 110-story skyscraper, instantly killing hundreds of people and trapping hundreds more on higher floors.
As the evacuation of the tower and its twin got underway, television cameras broadcast live images of what initially appeared to be a freak accident. Then, 17 minutes after the first plane hit, a second Boeing 767—United Airlines Flight 175—appeared in the sky, turned sharply toward the World Trade Center, and sliced into the South Tower between the 77th and 85th floors.
The collision caused a massive explosion that showered burning debris onto surrounding buildings and onto the streets below. It immediately became clear that the United States was under attack.
Osama bin Laden
How Decades of Instability Gave Rise to Al-Qaeda and the 9/11 Attacks
Learn how decades of violence and volatility created the conditions for Al-Qaeda to rise and attack the U.S. on September 11, 2001. Understand how U.S. intelligence failed to anticipate the 9/11 attacks, despite growing threats and warning signs.
The hijackers were members of al Qaeda. Fifteen were from Saudi Arabia, two were from the United Arab Emirates, one was from Egypt and one was from Lebanon. The attacks were orchestrated by al Qaeda leader Osama bin Laden, who cited America’s support of Israel, its involvement in the Persian Gulf War and its continued military presence in the Middle East as grievances.
Some of the hijackers had lived in the United States for more than a year and had taken flight training at American flight schools. Others had slipped into the country in the months before September 11 and acted as the “muscle” in the operation.
Where Did the 9/11 Planes Take Off From?
The 19 terrorists smuggled box-cutters and knives through security at three East Coast airports—Logan International Airport in Boston, Washington Dulles International Airport in Virginia and Newark International Airport in New Jersey—and boarded four early-morning flights bound for California, chosen because the planes were loaded with fuel for the long transcontinental journey. Soon after takeoff, the terrorists commandeered the four planes and took the controls, transforming ordinary passenger jets into weapons.
Pentagon Attack
Remembering 9/11: The Pentagon Attack
President George W. Bush, Donald Rumsfeld and others look back on the attack on the Pentagon on September 11, 2001.
As millions watched the events unfolding in New York, American Airlines Flight 77 circled over Washington, D.C., before crashing into the west side of the Pentagon military headquarters at 9:37 a.m.
Jet fuel from the Boeing 757 ignited a devastating inferno that led to the structural collapse of a portion of the Pentagon's giant concrete building, which is the headquarters of the U.S. Department of Defense.
All told, 125 military personnel and civilians were killed at the Pentagon, along with all 64 people aboard the airliner.
Twin Towers Collapse
Less than 15 minutes after the terrorists struck the nerve center of the U.S. military, the horror in New York took a catastrophic turn when the South Tower of the World Trade Center collapsed in a massive cloud of dust and smoke.
The structural steel of the skyscraper, built to withstand winds in excess of 200 mph, was severely weakened by the combined effects of the aircraft impact and resulting fires.
At 10:28 a.m., the North Tower collapsed. Only 16 people who were inside the towers at the time of the collapse survived. Most were with a group of FDNY firefighters in the North Tower’s Stairwell B, which remained intact. One woman survived after the stairs she was rushing down disintegrated around her. Almost 10,000 others were treated for injuries, many severe.
9/11: Pedestrians Flee Twin Towers Area
This video clip provided to "History Uncut" was taken immediately after the planes struck the two World Trade Center towers. We glimpse into the harrowing images of Manhattan that are not often shown in news broadcasts: a cameraman's frantic shadow fleeing the scene of disaster, emergency vehicles rendered unrecognizable by debris, and members of the NYPD who attempt to make sense out of the destruction.
Flight 93
Meanwhile, a fourth California-bound plane—United Airlines Flight 93—was hijacked about 45 minutes after leaving Newark International Airport in New Jersey. Because the plane had been delayed before takeoff, passengers and crew members learned of the attacks in New York and Washington during calls to the ground.
After learning about the earlier attacks, a group of passengers and crew members decided to fight back against the hijackers.
One of the passengers, Thomas Burnett Jr., told his wife over the phone that “I know we’re all going to die. There’s three of us who are going to do something about it. I love you, honey.” Another passenger—Todd Beamer—was heard saying “Are you guys ready? Let’s roll” over an open line.
The Todd Beamer Story "Let's Roll"
The incredible story of Todd Beamer's call to GTE Operator and the heroism on Flight 93.
Sandy Bradshaw, a flight attendant, called her husband and explained that she had slipped into a galley and was filling pitchers with boiling water. Her last words to him were “Everyone’s running to first class. I’ve got to go. Bye.”
The passengers and crew fought back against the four hijackers and may have tried to breach the cockpit using a fire extinguisher. As the counterattack continued, the hijackers rolled the plane onto its back and sent it into a steep dive. The plane crashed in a rural field near Shanksville in western Pennsylvania at 10:03 a.m., traveling about 563 mph.
All 44 people aboard were killed. Evidence indicates that the hijackers were headed for Washington, D.C., most likely targeting the U.S. Capitol, although the White House has also been identified as a possible target.
How Many People Died in the 9/11 Attacks?
A total of 2,996 people were killed in the 9/11 attacks, including the 19 hijackers aboard the four airplanes. The victims included citizens of more than 90 countries.
At the World Trade Center, 2,753 people were killed in the attacks, including 343 FDNY firefighters, 23 New York City police officers and 37 Port Authority police officers who were struggling to complete an evacuation of the buildings and save the office workers trapped on higher floors.
At the Pentagon, 189 people were killed, including 64 people aboard American Airlines Flight 77, the airliner that struck the building. On Flight 93, 44 people were killed when the hijackers crashed the plane in Pennsylvania.
After 9/11: Fifteen Septembers Later
How has the United States changed in the fifteen years since September 11, 2001? How will it continue to grow?
America Responds to the Attacks
At 7 p.m., President George W. Bush, who was in Florida at the time of the attacks and had spent the day being shuttled around the country because of security concerns, returned to the White House.
At 8:30 p.m., he delivered a televised address from the Oval Office, declaring, “Terrorist attacks can shake the foundations of our biggest buildings, but they cannot touch the foundation of America. These acts shatter steel, but they cannot dent the steel of American resolve.”
Signaling the U.S. response to come, Bush declared, “We will make no distinction between the terrorists who committed these acts and those who harbor them.”
Operation Enduring Freedom, the American-led international effort to oust the Taliban regime in Afghanistan and dismantle al Qaeda’s network there, began on October 7. Within two months, U.S. and allied Afghan forces had driven the Taliban from power, but the war continued as the Taliban regrouped and launched an insurgency, with leaders and fighters operating from sanctuaries in neighboring Pakistan.
Osama bin Laden, the mastermind behind the September 11 attacks, remained at large until May 2, 2011, when he was finally tracked down and killed by U.S. forces at a compound in Abbottabad, Pakistan. In June 2011, President Barack Obama announced the beginning a phased withdrawal of U.S. troops from Afghanistan; the last U.S. military forces left the country on August 30, 2021.
Department of Homeland Security Is Created
In the wake of security fears raised by 9/11 and the mailing of letters containing anthrax that killed five people and sickened 17 others, the Homeland Security Act of 2002 created the Department of Homeland Security. It was signed into law by President George W. Bush on November 25, 2002. Today, the Department of Homeland Security is a Cabinet department responsible for counterterrorism, border and immigration security, cybersecurity and disaster response, among other duties.
The act was followed two days later by the formation of the National Commission on Terrorist Attacks Upon the United States. The bipartisan “9/11 Commission,” as it came to be known, was charged with investigating the events that led up to September 11. The 9/11 Commission Report was released on July 22, 2004. It named Khalid Sheikh Mohammed, the mastermind behind 9/11, “the principal architect of the 9/11 attacks.”
Mohammed worked with and eventually led al Qaeda’s media committee while overseeing the planning of the 9/11 attacks. He was captured on March 1, 2003, in Rawalpindi, Pakistan, in an operation involving Pakistani authorities and the CIA. He was subsequently held at secret CIA detention sites, where he was subjected to so-called enhanced interrogation techniques, including waterboarding. In 2006, he was transferred to the U.S. detention facility at Guantánamo Bay, Cuba. Mohammed and four other men were later charged before a military commission with offenses related to the 9/11 attacks.
In August 2019, a U.S. military judge at Guantánamo Bay scheduled their trial to begin in January 2021, but proceedings were delayed, in part because of the COVID-19 pandemic. After years of further legal proceedings, a military judge in August 2026 set a new trial date of June 5, 2028, for Mohammed and three co-defendants.
Economic Impact of 9/11
The 9/11 attacks had an immediate negative effect on the U.S. economy. Many Wall Street institutions, including the New York Stock Exchange, were closed in the aftermath of the attacks. On the first day of trading after the attacks, the Dow Jones Industrial Average fell 7.1 percent, or 684 points. New York City’s economy alone lost 143,000 jobs a month and $2.8 billion in wages in the first three months. The heaviest losses were in finance and air transportation, which accounted for 60 percent of the lost jobs. The estimated cost of the World Trade Center site damage was $60 billion. The cost of removing debris at Ground Zero was $750 million.
Victim Compensation Fund
Thousands of first responders and people who worked or lived in lower Manhattan near Ground Zero were exposed to toxic dust, debris and other contaminants released when the towers collapsed and during the cleanup that followed. By the end of 2018, more than 10,000 members of the World Trade Center Health Program had cancers certified as 9/11-related.
From 2001 to 2004, the September 11th Victim Compensation Fund awarded more than $7 billion to the families of people killed and to thousands of people injured in the attacks. The fund was reactivated on January 2, 2011, when President Barack Obama signed the James Zadroga 9/11 Health and Compensation Act of 2010 into law. Named for James Zadroga, a New York City police officer who died after developing respiratory disease following his work at Ground Zero, the law established the World Trade Center Health Program and reactivated the Victim Compensation Fund for 9/11 responders and survivors.
In 2015, Congress reauthorized the World Trade Center Health Program for 75 years and extended the September 11th Victim Compensation Fund for five years, adding $4.6 billion to the fund. The Victim Compensation Fund was set to stop accepting claims in December 2020.
On July 29, 2019, President Donald Trump signed a law permanently authorizing the September 11 Victim Compensation Fund and extending its claim-filing deadline to 2090. Previously, administrators had cut some awards by 50 percent to 70 percent as the $7.375 billion in available funding was projected to run short. Prominent advocates for the fund included comedian Jon Stewart, 9/11 first responder John Feal and retired New York Police Department detective and 9/11 responder Luis Alvarez, who died of cancer 18 days after testifying before Congress.
Anniversary and Memorial
The 9/11 Survivor Tree
In the aftermath of the September 11, 2001, attacks, a callery pear tree emerged from the rubble.
On December 18, 2001, September 11 was designated as Patriot Day to commemorate the anniversary of the 9/11 attacks. In 2009, September 11 was also designated as a National Day of Service and Remembrance.
The first memorials to September 11 came in the immediate wake of the attacks, with candlelight vigils and flower tributes at U.S. embassies around the world. In Great Britain, the American national anthem was played during the changing of the guard at Buckingham Palace. Queen Elizabeth II sang along during a memorial service at St. Paul’s Cathedral the following day. Rio de Janeiro put up billboards showing the city’s Christ the Redeemer statue embracing the New York City skyline.
For the first anniversary of the attacks in New York City in 2002, two bright columns of light were beamed into the sky near the site of the Twin Towers. The “Tribute in Light” became an annual installation run by the Municipal Art Society of New York. On clear nights, the beams are visible from more than 60 miles away.
A World Trade Center Site Memorial Competition was held to select a design for a permanent memorial to the victims of 9/11. The winning design by Michael Arad, “Reflecting Absence,” occupies the eight-acre 9/11 Memorial plaza. It features two reflecting pools set within the footprints of the Twin Towers, with waterfalls cascading into them.
The names of all 2,977 victims are engraved on the 152 bronze panels surrounding the pools, arranged according to where individuals were on the day of the attacks and by relationships among the victims, so colleagues, friends and people on the same flight can be memorialized together. The names of the six people killed in the World Trade Center bombing on February 26, 1993, are also engraved on the panels. The 9/11 Memorial opened to the public on September 11, 2011, to commemorate the 10th anniversary of 9/11. The National September 11 Memorial & Museum opened on the original World Trade Center site in May 2014. One World Trade Center, also on the original World Trade Center site, opened in November 2014.
Photo Galleries
Hear extraordinary stories of resilience and healing from the children impacted on 9/11—their life and legacy 20 years later.
Sources
"Study Confirms 9/11 Impact on New York City Economy." The New York Times "September 11: nearly 10,000 people affected by 'cesspool of cancer.'" The Guardian. "Congress passes 9/11 Victim Compensation Fund extension championed by Jon Stewart." CNN.com The Encyclopedia of 9/11. New York Magazine. FAQ About 9/11. 9/11 Memorial. September 11th Terror Attacks Fast Facts. CNN. 9/11 Death Statistics. StatisticBrain.com.
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Citation Information
- Article Title
- September 11 Attacks
- Author
- HISTORY.com Editors
- Website Name
- History
- Date Accessed
- October 21, 2026
- Publisher
- A&E Television Networks
- Last Updated
- September 09, 2026
- Original Published Date
- February 17, 2010