11 September attacks

11 September attacks
Flickr user Michael Foran · CC BY 2.0 · source
Title	11 September attacks
Date	11 September 2001
Locations	New York City; Arlington County, Virginia; Shanksville, Pennsylvania
Targets	World Trade Center; Pentagon; United Airlines Flight 93
Fatalities	~2,977 (including hijackers)
Perpetrators	al-Qaeda
Weapons	Hijacked commercial airliners

11 September attacks were a series of four coordinated terrorist hijackings and suicide attacks on 11 September 2001 that targeted tall buildings and symbols of state power and finance in the United States. The attacks used commercial airliners as improvised weapons, causing catastrophic structural failures, mass casualties, and immediate involvement by Federal Bureau of Investigation, Central Intelligence Agency, United States Department of Defense, and emergency services in New York City, Arlington County, Virginia, and Somerset County, Pennsylvania. The events precipitated major military, legal, and intelligence actions involving actors such as George W. Bush, Tony Blair, NATO, and United Nations Security Council members.

Background

Planning traced to operatives associated with Osama bin Laden and the al-Qaeda network, which had carried out prior attacks including the 1993 bombing of the World Trade Center and the 1998 bombings of the United States embassies in Dar es Salaam and Nairobi. Preceding incidents such as the 2000 attack on the USS Cole in Aden and plots uncovered by FBI investigations in the 1990s signaled growing transnational threats linked to training camps in Afghanistan and sanctuaries in Sudan. Intelligence exchanges among agencies like the National Security Agency and policy debates in administrations of Bill Clinton and George W. Bush shaped responses to al-Qaeda's evolving capabilities.

Attacks

On the morning of 11 September 2001, 19 hijackers associated with al-Qaeda seized four passenger jets: American Airlines Flight 11, United Airlines Flight 175, American Airlines Flight 77, and United Airlines Flight 93. Two aircraft, Flights 11 and 175, were flown into the North and South Towers of the World Trade Center complex in Lower Manhattan, causing progressive collapse of both towers and severe damage to adjacent structures including 7 World Trade Center. Flight 77 struck the Pentagon in Arlington County, Virginia, damaging portions of the Department of Defense headquarters. Flight 93 crashed near Shanksville, Pennsylvania after passengers attempted to retake control; subsequent investigations referenced cockpit voice recorders and passenger phone calls. First responders from agencies such as the New York City Fire Department, Port Authority of New York and New Jersey Police Department, and New York City Police Department executed search, rescue, and evacuation operations amid unprecedented destruction.

Immediate aftermath and response

Federal and local authorities implemented emergency plans involving the Federal Emergency Management Agency, airspace was closed by Federal Aviation Administration, and leaders including Mayor Rudy Giuliani and President George W. Bush coordinated crisis management. The North Atlantic Treaty Organization invoked Article 5 for the first time in its history, prompting military deployments by member states including United Kingdom forces under Prime Minister Tony Blair and allied support from Canada and Australia. Financial markets such as the New York Stock Exchange suspended trading; major corporations including Citigroup, Goldman Sachs, and Lehman Brothers relocated operations or activated contingency plans. Emergency medical centers like NewYork–Presbyterian Hospital and St. Vincent's Hospital treated thousands of injured, while search operations at Ground Zero involved agencies including the Occupational Safety and Health Administration.

Investigations and legal proceedings

Criminal and intelligence investigations were led by the Federal Bureau of Investigation with prosecutions involving material support, terrorism financing, and conspiracy charges linked to organizations such as al-Qaeda and financiers identified in inquiries by Congress and the 9/11 Commission. The National Commission on Terrorist Attacks Upon the United States produced the 9/11 Commission Report outlining failures in intelligence sharing, and recommendations affecting the creation of the Director of National Intelligence and restructuring of agencies including the Central Intelligence Agency and Federal Bureau of Investigation. Legal actions included civil litigation by families against airlines like American Airlines and United Airlines, in addition to military commissions and detentions at Guantanamo Bay under policies of the Department of Defense and executive directives such as the Authorization for Use of Military Force.

Victims and casualties

Approximately 2,977 people were killed, including passengers, first responders, office workers, and members of the hijacker teams. Victims represented many nationalities and included employees of firms such as Cantor Fitzgerald, Marsh & McLennan Companies, and Aon Corporation. The collapse and fires produced long-term health consequences for responders and survivors, leading to programs under the James Zadroga 9/11 Health and Compensation Act and monitoring by institutions like the National Institute for Occupational Safety and Health. Recovery of remains and identification efforts involved the Office of Chief Medical Examiner of the City of New York and forensic partners using DNA analysis and collaborations with international laboratories.

Impact and consequences

The attacks triggered the War on Terror, including the United States invasion of Afghanistan aimed at dismantling al-Qaeda and removing Taliban protection of its leadership. Subsequent operations involved coalitions such as the International Security Assistance Force and later NATO-led International Security Assistance Force transitions. Domestic policy shifts included the establishment of the Department of Homeland Security, passage of the USA PATRIOT Act, and expanded surveillance by the National Security Agency. Geopolitical consequences influenced relations with states including Pakistan, Saudi Arabia, and Iraq, and precipitated debates over detention policy, rendition, and counterterrorism strategy that involved judicial scrutiny by the United States Supreme Court.

Commemoration and memorials

Memorials and museums include the National September 11 Memorial & Museum at the World Trade Center site, the Pentagon Memorial in Arlington County, and the Flight 93 National Memorial in Pennsylvania. Annual observances involve moments of silence, services attended by officials such as successive United States Presidents and local leaders, and commemorative events coordinated by organizations like the 9/11 Memorial & Museum and victims' advocacy groups including the 9/11 Families United. Cultural responses involved works by creators connected to institutions such as Lincoln Center and publications addressing the events by journalists from outlets like The New York Times and The Washington Post.

Category:Terrorist incidents in the United States Category:2001 in New York City