September 11 attacks (2001)

September 11 attacks (2001)
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Title	September 11 attacks (2001)
Caption	Collapse of the World Trade Center North Tower and South Tower in New York City on September 11, 2001
Date	September 11, 2001
Locations	New York City, Arlington County, Virginia, Shanksville, Pennsylvania
Targets	World Trade Center, Pentagon (building), United Airlines Flight 175, American Airlines Flight 11, United Airlines Flight 93, American Airlines Flight 77
Fatalities	2,977 (approximate)
Perpetrators	al-Qaeda
Weapons	Hijacked commercial airliners

September 11 attacks (2001) The September 11 attacks (2001) were a series of four coordinated terrorism attacks executed by al-Qaeda operatives on September 11, 2001, that targeted the United States and led to the deaths of nearly 3,000 people. The attacks struck the World Trade Center in New York City, the Pentagon (building) in Arlington County, Virginia, and resulted in the crash of a hijacked airliner in Shanksville, Pennsylvania, prompting immediate national and international military, intelligence, and policy responses.

Background

In the years preceding September 11, senior al-Qaeda leaders including Osama bin Laden, Ayman al-Zawahiri, and Khalid Sheikh Mohammed developed an aspirational campaign inspired by prior incidents such as the 1993 World Trade Center bombing, the 1998 United States embassy bombings, and the 2000 attack on the USS Cole. U.S. intelligence agencies including the Central Intelligence Agency, the Federal Bureau of Investigation, and the National Security Agency monitored extremist networks and figures such as Richard Reid and Ramzi Yousef, while policy debates in the Clinton administration and the George W. Bush administration concerned threats from transnational Islamist militancy. International law enforcement cooperation involving Interpol, MI6, and other services tracked flight-training activity and financial transfers linked to facilitators in countries such as Afghanistan, Pakistan, and Saudi Arabia, where elements of the Taliban (1994–2001) provided sanctuary to al-Qaeda leadership.

Attacks

On the morning of September 11, members of an al-Qaeda cell led operationally by Khalid Sheikh Mohammed hijacked four commercial airliners departing from airports including Logan International Airport, Newark Liberty International Airport, and Washington Dulles International Airport. American Airlines Flight 11 and United Airlines Flight 175 were flown into the North Tower and South Tower of the World Trade Center respectively, causing catastrophic structural failure and the eventual collapse of both towers and extensive destruction to surrounding structures such as World Financial Center and St. Paul's Chapel. American Airlines Flight 77 was crashed into the Pentagon (building), producing fire and structural damage to the Department of Defense headquarters. United Airlines Flight 93 crashed near Shanksville, Pennsylvania after passengers led an uprising influenced by crew warnings and communications with authorities; passengers on Flight 93 included individuals later commemorated at the Flight 93 National Memorial.

Immediate aftermath and response

In the immediate aftermath, emergency responders from agencies including the New York City Fire Department, the Port Authority of New York and New Jersey, the Metropolitan Police Department of the District of Columbia, and the United States Secret Service executed large-scale search, rescue, and recovery efforts amid ongoing hazards such as fires and structural collapse. President George W. Bush addressed the nation, invoking statutes such as the Authorization for Use of Military Force and coordinating with allies including United Kingdom, NATO, and leaders like Tony Blair, Jacques Chirac, and Vladimir Putin to frame a collective response. Air travel was halted by directives from the Federal Aviation Administration, and major financial hubs including the New York Stock Exchange and institutions such as Goldman Sachs and Morgan Stanley suspended operations. Public discourse engaged figures from media organizations including The New York Times, CNN, and BBC News while humanitarian responses involved American Red Cross, FEMA, and international aid agencies.

Investigations and accountability

Investigations were led domestically by the Federal Bureau of Investigation and the National Transportation Safety Board with congressional oversight by the United States House Committee on Transportation and Infrastructure and the United States Senate Committee on Intelligence. The 9/11 Commission (formally the National Commission on Terrorist Attacks Upon the United States) published a comprehensive report detailing intelligence failures, policy decisions, and recommendations involving actors such as Condoleezza Rice, Colin Powell, Donald Rumsfeld, and Richard Clarke. Criminal and military responses included the invasion of Afghanistan targeting al-Qaeda and the Taliban (1994–2001), capture operations by forces including United States Special Operations Command, detentions at Guantanamo Bay Naval Base, and legal proceedings addressing terrorism financing involving banks such as Mellon Financial and entities linked to individuals from Saudi Arabia. High-profile manhunts and actions culminated in later events including the 2011 raid on Osama bin Laden by Navy SEALs of SEAL Team Six.

Impact and long-term consequences

The attacks precipitated enduring changes in U.S. domestic policy, international relations, and security practices: legislative actions including the USA PATRIOT Act reconfigured surveillance authorities involving the National Security Agency and the Department of Homeland Security, while institutional reforms created agencies such as the Transportation Security Administration and reinforced roles for the Federal Aviation Administration. The Global War on Terror led to prolonged military campaigns in Afghanistan and Iraq, influencing geopolitics with effects on energy markets, alliances such as NATO, and regional dynamics involving Iran, Pakistan, and Syria. Cultural and legal debates engaged civil liberties advocates, academic institutions such as Harvard University and Columbia University, and arts organizations responding through memorials like the National September 11 Memorial & Museum and commemorative works by artists including Kehinde Wiley and writers published in The Atlantic. Economically, disruptions affected markets including the New York Stock Exchange and industries like aviation and insurance, while public health and urban planning addressed long-term consequences for first responders and survivors through programs administered by agencies such as the Centers for Disease Control and Prevention and the National Institute for Occupational Safety and Health.

Category:2001 crimes in the United States