September 11 attacks
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The September 11 attacks were a series of airline hijackings and suicide attacks committed in 2001 by 19 terrorists associated with the Islamic extremist group al-Qaeda. It was the deadliest terrorist attack on U.S. soil; nearly 3,000 people were killed. The attacks involved the hijacking of four planes, three of which were used to strike significant U.S. sites. American Airlines flight 11 and United Airlines flight 175 were flown into the World Trade Center’s north and south towers, respectively, and American Airlines flight 77 hit the Pentagon. United Airlines flight 93 crashed in a field near Shanksville, Pennsylvania, after passengers attempted to overpower the hijackers. The plane was believed to be headed to the U.S. Capitol building in Washington, D.C.
The exact number of victims—particularly the number of those killed at the World Trade Center—is not definitively known. However, the official death toll, after numerous revisions and not including the 19 terrorists, was set at 2,977 people. At the World Trade Center in New York City, 2,753 people died, of whom 343 were firefighters. The death toll at the Pentagon near Washington, D.C., was 184, and 40 individuals died outside Shanksville, Pennsylvania.
Al-Qaeda leader Osama bin Laden is considered the mastermind of the attacks, though Khalid Sheikh Mohammed was the operational planner. Mohammed came up with the tactical innovation of using hijacked planes to attack the United States, and al-Qaeda provided the personnel, money, and logistical support to execute the operation. Mohammed Atta was selected to head the operation. He and 18 other terrorists, most of whom were from Saudi Arabia, established themselves in the United States, where some received commercial flight training. All 19 hijackers died in the attacks, bin Laden was killed by U.S. forces in 2011, and Mohammed was captured in 2003.
The attacks had a profound and lasting impact on the country, especially regarding its foreign and domestic policies. U.S. Pres. George W. Bush declared a global “war on terrorism,” and lengthy wars in Afghanistan and Iraq followed. Meanwhile, security measures within the United States were tightened considerably, especially at airports. To help facilitate the domestic response, Congress quickly passed the controversial USA PATRIOT Act, which significantly expanded the search and surveillance powers of federal law-enforcement and intelligence agencies. Additionally, a cabinet-level Department of Homeland Security was created.
September 11 attacks, also called 9/11 attacks, series of airline hijackings and suicide attacks committed in 2001 by 19 militants associated with the Islamic extremist group al-Qaeda against targets in the United States, the deadliest terrorist attacks on American soil in U.S. history. The attacks against New York City and Washington, D.C., caused extensive death and destruction and triggered an enormous U.S. effort to combat terrorism. Some 2,750 people were killed in New York, 184 at the Pentagon, and 40 in Pennsylvania (where one of the hijacked planes crashed after the passengers attempted to retake the plane); all 19 terrorists died (see Researcher’s Note: September 11 attacks). Police and fire departments in New York were especially hard-hit: hundreds had rushed to the scene of the attacks, and more than 400 police officers and firefighters were killed.
The plot
The September 11 attacks were precipitated in large part because Osama bin Laden, the leader of the militant Islamic organization al-Qaeda, held naive beliefs about the United States in the run-up to the attacks. Abu Walid al-Masri, an Egyptian who was a bin Laden associate in Afghanistan in the 1980s and ’90s, explained that, in the years prior to the attacks, bin Laden became increasingly convinced that America was weak. “He believed that the United States was much weaker than some of those around him thought,” Masri remembered, and “as evidence he referred to what happened to the United States in Beirut when the bombing of the Marines base led them to flee from Lebanon,” referring to the destruction of the marine barracks there in 1983 (see 1983 Beirut barracks bombings), which killed 241 American servicemen. Bin Laden believed that the United States was a “paper tiger,” a belief shaped not just by America’s departure from Lebanon following the marine barracks bombing but also by the withdrawal of American forces from Somalia in 1993, following the deaths of 18 U.S. servicemen in Mogadishu, and the American pullout from Vietnam in the 1970s.
The key operational planner of the September 11 attacks was Khalid Sheikh Mohammed (often referred to simply as “KSM” in the later 9/11 Commission Report and in the media), who had spent his youth in Kuwait. Khalid Sheikh Mohammed became active in the Muslim Brotherhood, which he joined at age 16, and then he went to the United States to attend college, receiving a degree from North Carolina Agricultural and Technical State University in 1986. Afterward he traveled to Pakistan and then Afghanistan to wage jihad against the Soviet Union, which had launched an invasion against Afghanistan in 1979.
According to Yosri Fouda, a journalist at the Arabic-language cable television channel Al Jazeera who interviewed him in 2002, Khalid Sheikh Mohammed planned to blow up some dozen American planes in Asia during the mid-1990s, a plot (known as “ Bojinka”) that failed, “but the dream of Khalid Sheikh Mohammed never faded. And I think by putting his hand in the hands of bin Laden, he realized that now he stood a chance of bringing about his long awaited dream.”
In 1996 Khalid Sheikh Mohammed met bin Laden in Tora Bora, Afghanistan. The 9-11 Commission (formally the National Commission on Terrorist Attacks Upon the United States), set up in 2002 by Pres. George W. Bush and the U.S. Congress to investigate the attacks of 2001, explained that it was then that Khalid Sheikh Mohammed “presented a proposal for an operation that would involve training pilots who would crash planes into buildings in the United States.” Khalid Sheikh Mohammed dreamed up the tactical innovation of using hijacked planes to attack the United States, al-Qaeda provided the personnel, money, and logistical support to execute the operation, and bin Laden wove the attacks on New York and Washington into a larger strategic framework of attacking the “far enemy”—the United States—in order to bring about regime change across the Middle East.
The September 11 plot demonstrated that al-Qaeda was an organization of global reach. The plot played out across the globe with planning meetings in Malaysia, operatives taking flight lessons in the United States, coordination by plot leaders based in Hamburg, Germany, money transfers from Dubai, and recruitment of suicide operatives from countries around the Middle East—all activities that were ultimately overseen by al-Qaeda’s leaders in Afghanistan.
Key parts of the September 11 plot took shape in Hamburg. Four of the key pilots and planners in the “Hamburg cell” who would take operational control of the September 11 attacks, including the lead hijacker Mohammed Atta, had a chance meeting on a train in Germany in 1999 with an Islamist militant who struck up a conversation with them about fighting jihad in the Russian republic of Chechnya. The militant put the Hamburg cell in touch with an al-Qaeda operative living in Germany who explained that it was difficult to get to Chechnya at that time because many travelers were being detained in Georgia. He recommended they go to Afghanistan instead.
Although Afghanistan was critical to the rise of al-Qaeda, it was the experience that some of the plotters acquired in the West that made them simultaneously more zealous and better equipped to carry out the attacks. Three of the four plotters who would pilot the hijacked planes on September 11 and one of the key planners, Ramzi Binalshibh, became more radical while living in Hamburg. Some combination of perceived or real discrimination, alienation, and homesickness seems to have turned them all in a more militant direction. Increasingly cutting themselves off from the outside world, they gradually radicalized each other, and eventually the friends decided to wage battle in bin Laden’s global jihad, setting off for Afghanistan in 1999 in search of al-Qaeda.
Atta and the other members of the Hamburg group arrived in Afghanistan in 1999 right at the moment that the September 11 plot was beginning to take shape. Bin Laden and his military commander Muhammad Atef realized that Atta and his fellow Western-educated jihadists were far better suited to lead the attacks on Washington and New York than the men they had already recruited, leading bin Laden to appoint Atta to head the operation.
The hijackers, most of whom were from Saudi Arabia, established themselves in the United States, many well in advance of the attacks. They traveled in small groups, and some of them received commercial flight training.
Throughout his stay in the United States, Atta kept Binalshibh updated on the plot’s progress via e-mail. To cloak his activities, Atta wrote the messages as if he were writing to his girlfriend “Jenny,” using innocuous code to inform Binalshibh that they were almost complete in their training and readiness for the attacks. Atta wrote in one message, “The first semester commences in three weeks…Nineteen certificates for private education and four exams.” The referenced 19 “certificates” were code that identified the 19 al-Qaeda hijackers, while the four “exams” identified the targets of the attacks.
In the early morning of August 29, 2001, Atta called Binalshibh and said he had a riddle that he was trying to solve: “Two sticks, a dash and a cake with a stick down—what is it?” After considering the question, Binalshibh realized that Atta was telling him that the attacks would occur in two weeks—the two sticks being the number 11 and the cake with a stick down a 9. Putting it together, it meant that the attacks would occur on 11-9, or 11 September (in most countries the day precedes the month in numeric dates, but in the United States the month precedes the day; hence, it was 9-11 in the United States). On September 5 Binalshibh left Germany for Pakistan. Once there he sent a messenger to Afghanistan to inform bin Laden about both the day of the attack and its scope.
The September 11 terrorist attacks
The September 11 terrorist attacks
The day that defined the beginning of the 21st Century for Americans
On September 11, 2001, 2,977 people were killed in the deadliest terrorist attacks in American history.
The World Trade Center in March, 2001 Wikimedia Commons
The moment shocked the nation. Two planes, hijacked by Islamic jihadists vowing death to all Americans, plowed into both towers at the World Trade Center in New York. Another plane was flown into the Pentagon in Washington, DC. A fourth plane, presumably headed for the White House or the U.S. Capitol, was heroically diverted by passengers and ended up crashing in an empty field in Pennsylvania. After reports of the first plane hitting the North Tower, millions watched the second plane hit the South Tower on live television.
It was a terrifying, startling, and humbling event for the country. The 9/11 attacks were the deadliest on American soil since the shock attack at Pearl Harbor 60 years before, and the sense of outrage was reminiscent of that moment. The attacks in New York occurred in the country’s busiest city on a busy workday. And the staggered nature of the attacks meant that news footage captured almost everything as it happened, ensuring that millions of Americans saw the events precisely as they unfolded.
Flight paths of the hijacked planes Wikimedia Commons
Timeline
September 11, 2001
7:59 AM – Flight 11 takes off from Boston, headed for Los Angeles, California. There are 76 passengers, 11 crew members, and 5 hijackers on board.
8:15 AM – United Airlines Flight 175 takes off from Boston, also headed for Los Angeles. There are 51 passengers, 9 crew members, and 5 hijackers on board.
8:20 AM – American Airlines Flight 77 takes off from Dulles, outside of Washington, DC, headed for Los Angeles. There are 53 passengers, 6 crew members, and 5 hijackers on board.
8:42 AM – United Flight 93 takes off from Newark, New Jersey, after a delay due to routine traffic. It was headed for San Francisco, California. There are 33 passengers, 7 crew members, and 4 hijackers are on board.
8:46 AM – Flight 11 crashes into the World Trade Center’s North Tower. All passengers aboard are instantly killed, and employees of the WTC are trapped above the 91 st floor.
9:03 AM – Flight 175 crashes into the WTC’s South Tower. All passengers aboard are killed instantly and so are an unknown number of people in the tower.
9:05 AM – President George W. Bush, in an elementary school classroom in Florida, is informed about the hit on the second tower. His chief of staff, Andrew Card, whispers the chilling news into the president’s ear. Bush later wrote about his response: “I made the decision not to jump up immediately and leave the classroom. I didn’t want to rattle the kids. I wanted to project a sense of calm… I had been in enough crises to know that the first thing the leader has to do is to project calm.” (Miller Center)
President Bush participates in a reading demonstration on the morning of September 11 at Emma E. Booker Elementary School in Sarasota, Florida Courtesy of George W. Bush Presidential Library and Museum
9:37 AM – Flight 77 crashes into the Pentagon. All passengers aboard are instantly killed and so are 125 civilian and military personnel in the building.
9:45 AM – US airspace is shut down under Operation Yellow Ribbon. All civilian aircraft are ordered to land at the nearest airport.
President Bush at Emma E. Booker Elementary School, receiving details about the planes hitting the Twin Towers Wikimedia Commons
9:55 AM – Air Force One with President George W. Bush aboard takes off from Florida.
9:57 AM – Passengers aboard Flight 93 begin to run up toward the cockpit. Jarrah, the pilot, begins to roll the plane back and forth in an attempt to destabilize the revolt.
9:59 AM – The South Tower of the World Trade Center collapses.
Before and after the South Tower collapse Wikimedia Commons
10:02 AM – Flight 93 plows into an empty field in Shanksville, Pennsylvania. Although its ultimate target is unknown, it was likely heading for either the White House or the US Capitol.
The site of Flight 93’s crash Wikimedia Commons
10:18 AM – President Bush authorizes any non-grounded planes to be shot down. At that time, all four hijacked planes had already crashed but the president’s team was operating under the impression that Flight 93 was still in the air.
10:28 AM – The North Tower of the World Trade Center collapses.
10:53 AM – Secretary of Defense Donald Rumsfeld orders the US military to move to a higher state of alert, going to DEFCON 3.
11:45 AM – Air Force 1 lands at Barksdale Air Force Base near Shreveport, Louisiana.
12:15 PM – Airspace in the United States is completely free of all commercial and private flights.
1:30 PM – Air Force 1 leaves Barksdale.
2:30 PM – Rudy Giuliani, the mayor of New York City, visits the fallen Twin Towers of the World Trade Center at what becomes known as Ground Zero.
Mayor Giuliani at Ground Zero with Secretary of Defense Donald Rumsfeld Wikimedia Commons
3:00 PM – Air Force 1 lands at Offutt Air Force Base in Nebraska, and President Bush is immediately taken to a secure bunker that is capable of withstanding a nuclear attack.
4:30 PM – Air Force 1 leaves Offutt and heads back toward Andrews Air Force base near Washington, DC.
President Bush confers with Vice President Cheney from Air Force One on the flight from Offutt Air Force Base to Offutt Air Force Base George W. Bush Presidential Library and Museum (P77091-18)
5:30 PM – Building 7 of the World Trade Center collapses.
Helicopter photo of Ground Zero on October 8, 2001 Wikimedia Commons
Background
Although to many Americans 9/11 seemed like a random act of terror, the roots of the event had been developing for years. A combination of factors that coalesced in the late 1990s led the catastrophic event. These factors included regional conditions in the Middle East that motivated the perpetrators, as well as intelligence lapses and failures that left the United States vulnerable.
Osama bin Laden in November, 2001 Wikimedia Commons
Osama Bin Laden was relatively unknown in the United States before 9/11, even as he was amassing popularity, followers, and fame in the Middle East during the 1990s. In 1988, he was one of the founders of al Qaeda, a militant Islamic terrorist organization that organized and carried out the 9/11 attacks. Bin Laden called for indiscriminate killing of all Americans who, he claimed, were “the worst thieves in the world today” (9/11 Report, page 47). It was the perfect historical moment for that rallying cry.
Throughout the 20th century, a wave of secular, nationalist revolutions swept through the Middle East, taking root in Egypt, Libya, Iraq, Yemen, and other countries. While these movements were awash in promising ideology, the new regimes quickly became autocratic and suppressed dissent. Their critics turned to violent revolution to express their dissatisfaction with the secular governments.
At the same time, social malaise, especially among young men who were struggling to find decent jobs and start their own families in corrupt oil states, provided easy targets for radicalization. Bin Laden’s message that America was the “head of the snake” and the root of all society’s problems resonated well with the discontent.
By the mid-1990s, Bin Laden was the head of al Qaeda, a multifaceted and highly developed terrorist network carrying out attack after attack on Americans in the Middle East. It was a new type of terrorism to which the US intelligence agencies struggled to adapt. Much of the intelligence community had not even imaged the specific type of hijacking and terrorism carried out on 9/11. They were preparing for threats such as the 1993 bombing of the World Trade Center and bombing in 2000 of the USS Cole.
Aftermath of the 1993 WTC Bombing Wikimedia Commons
Much of the intelligence community’s focus was on reactive law enforcement activity rather than proactive countering of terrorism. A telling quote from the 9/11 commission report focuses on the lack of a proactive response: “The process was meant, by its nature, to mark for the public as the events finished – case solved, justice done. It was not designed to ask if the events might be harbingers of worse to come. Nor did it allow for aggregating and analyzing facts to see if they could provide clues to terrorist tactics more generally – methods of entry and finance, and mode of operation inside the United States” (Commission Report, p. 73).
Bin Laden had amassed substantial power due to conditions in the Middle East as well as his charismatic leadership, and the US intelligence community was underprepared for a 9/11 style attack. In the aftermath of 9/11, these two factors continued to affect US policy in the Middle East, particularly in Iraq.
Aftermath
The immediate response to 9/11 was the George W. Bush administration’s War on Terror, which began in Afghanistan as a retaliation against al Qaeda for carrying out the attack. The Bush administration soon expanded the War on Terror into Iraq, and the consequences of these wars continue to affect the Middle East to this day. Almost 20 years later, the United States is still at war in both Afghanistan and Iraq.
American Soldiers in Iraq, 2005 Wikimedia Commons
There were domestic long-term effects of 9/11 as well. Thousands of people struggle with cancer and lasting chronic health problems relating to the toxicity from Ground Zero, the site where the Twin Towers used to stand. The September 11 attacks also changed American air travel as airlines began to require stringent security checks designed to prevent the types of weapons the hijackers used from slipping through.
Finally, the 9/11 attacks resulted in changes to the federal government and an expansion of executive power. A new cabinet department, the Department of Homeland Security, was created, and the intelligence community was consolidated under the Director of National Intelligence to improve coordination between various agencies and departments. New legislation such as the USA Patriot Act expanded domestic security and surveillance, disrupted terrorist funding by cracking down on activities such as money laundering, and increased efficiency within the U.S. intelligence community.
The tragedy of September 11, 2001 will never be forgotten, and the aftermath is still continuing to unfold. The 9/11 Memorial and Museum opened on the site of the former World Trade Center on September 11, 2011, and features reflecting pools in the footprints of where the Twin Towers once stood.
