At around 9:30pm on September 11, 2001, George Tenet, director of the Central Intelligence Agency (CIA), told President George W. Bush and U.S. senior officials that the CIA's Counterterrorism Center had determined that Osama bin Laden and al-Qaeda were responsible for the September 11 attacks. Two weeks after the terrorist attacks on September 11, 2001, the Federal Bureau of Investigation connected the hijackers to al-Qaeda, a militant Salafist Islamist multi-national organization. In a number of video, audio, interview and printed statements, senior members of al-Qaeda have also asserted responsibility for organizing the September 11 attacks.
Identifying the hijackers
The FBI investigation into the attacks, codenamed operation PENTTBOM, identified the 19 hijackers within days, as they made little effort to conceal their names on flights, credit cards, and other records. By checking flight manifests and comparing them with other information, like watch lists, customs officials found the names of all 19 hijackers quickly.
Passengers and crew aboard the flights provided information about the hijackers while the hijacking was in progress. Two flight attendants on American Airlines Flight 11, Betty Ong and Madeline Amy Sweeney, contacted airline personnel on the ground. Sweeney provided the seat numbers of the hijackers, and descriptions of the men, identifying Mohamed Atta as one of the hijackers. A flight attendant on United Airlines Flight 175 called a United Airlines mechanic and reported that hijackers had killed the crew. While the hijacking was in progress on American Airlines Flight 77, several passengers, including a flight attendant, Renee May, contacted and reported details of the hijacking to persons on the ground. Sales clerks identified two individuals to whom they sold tickets on Flight 77 as the hijackers Hani Hanjour and Majed Moqed. During the hijacking of United Airlines Flight 93, Jeremy Glick identified the hijackers as Arabic-looking and carrying box-cutters.
Atta's luggage did not make the connection from his Portland flight to American Airlines Flight 11. In his suitcase, authorities found a handwritten letter in Arabic. As well, a handwritten letter was found at the crash site of United Airlines Flight 93 near Shanksville, Pennsylvania, and another in al-Hazmi's vehicle. When examining Atta's left-behind luggage, the FBI found important clues about the hijackers and their plans. Atta's luggage contained instructional videotapes for flying large aircraft, a fuel consumption calculator, and a flight plan, along with a copy of the Quran. His luggage also contained papers that revealed the identity of all 19 hijackers, along with a copy of Atta's last will and testament. The passport of hijacker Abdulaziz al-Omari was also found in Atta's luggage.
Various items of evidence were found in vehicles left behind at the airports, in luggage that did not make it onto the flights, and at the crash scenes. A rental car belonging to the hijackers was found at Boston's Logan International Airport, which contained an Arabic language flight manual and documents from Huffman Aviation in Florida. There, investigators found Atta and Marwan al-Shehhi's previous address in Hamburg, Germany. Nawaf al-Hazmi's 1988 blue Toyota Corolla was found on September 12 in Dulles International Airport's hourly parking lot. Inside the vehicle, authorities found a letter written by Atta, maps of Washington, D.C. and New York City, a cashier's check made out to a Phoenix flight school, four drawings of a Boeing 757 cockpit, a box cutter-type knife, and a page with notes and phone numbers.
In New York City, a passport belonging to Satam al-Suqami was found by a passerby before the towers collapsed, and given to a NYPD detective. The passports of two of the hijackers of Flight 93 were also found intact at the crash site.
Abu Jandal, who served as bin Laden's chief bodyguard for years, confirmed the identity of seven hijackers as al-Qaeda members during interrogations with the FBI on September 17. He had been jailed in a Yemeni prison since 2000.
On September 27, 2001, the FBI released photos of the 19 hijackers, along with information about the possible nationalities and aliases of many.
Assigning responsibility For several months following the September 11 attacks, no one claimed responsibility for the attacks. As such, primary responsibility initially fell solely upon the hijackers, all of whom were killed leaving no message, claim of responsibility, or explanation. As the media covered the attacks unfolding, many quickly speculated that bin Laden was behind the attacks. On the day of the attacks, the National Security Agency intercepted communications that pointed to bin Laden, as did German intelligence agencies. This helped rule out other immediate suspects, such as Croatian nationalists, who had planted a bomb in Grand Central Terminal on September 10, 1976.Katz, Samuel M. "Relentless Pursuit: The DSS and the manhunt for the al-Qaeda terrorists", 2002
Authorities in the United States and Britain also obtained electronic intercepts, including telephone conversations and electronic bank transfers, which indicate that Mohammed Atef, a bin Laden deputy, was a key figure in the planning of the 9/11 attacks. Intercepts were also obtained that revealed conversations that took place days before September 11 between bin Laden and an associate in Pakistan. In those conversations, the two referred to "an incident that would take place in America on, or around, September 11" and they discussed potential repercussions. In another conversation with an associate in Afghanistan, bin Laden discussed the "scale and effects of a forthcoming operation." These conversations did not specifically mention the World Trade Center or the Pentagon, or other specifics.
The investigators quickly linked the 19 men to the terrorist organization al-Qaeda. The New York Times reported on September 12 that: "Authorities said they had also identified accomplices in several cities who had helped plan and execute Tuesday's attacks. Officials said they knew who these people were and important biographical details about many of them. They prepared biographies of each identified member of the hijack teams, and began tracing the recent movements of the men." FBI agents in Florida investigating the hijackers quickly "descended on flight schools, neighborhoods and restaurants in pursuit of leads." At one flight school, "students said investigators were there within hours of Tuesday's attacks." The Washington Post later reported that "In the hours after Tuesday's bombings, investigators searched their files on [Satam] al-Suqami and [Ahmed] al-Ghamdi, noted the pair's ties to [Nabil] al-Marabh and launched a hunt for him."NucNews, Sep 21, 2001 .
Based on the evidence, authorities in the United States quickly asserted that Osama bin Laden and his al-Qaeda organization were solely responsible for the attacks, and other suspects were ruled out. The Government of the United Kingdom reached the same conclusion. Although he denied involvement in the attacks at first, Osama bin Laden claimed full responsibility in a 2004 video.
Author Laurie Mylroie, writing in the conservative political magazine The American Spectator in 2006, argued that Khalid Sheikh Mohammed and his family are the primary architects of 9/11 and similar attacks, that Khalid Sheikh Mohammed's association with Osama bin Laden is secondary, and that Al-Qaeda's claim of responsibility for the attack is after the fact and opportunistic. In an opposing point of view, former CIA officer Robert Baer, writing in Time magazine in 2007, asserted that the George W. Bush administration's publicizing of Khalid Sheikh Mohammed's claims of responsibility for 9/11 and numerous other acts was a mendacious attempt to claim that all of the significant actors in 9/11 had been caught.
Al-Qaeda and Osama bin Laden
Intelligence experts speak of a "short list" of prime suspects—groups that possess both the means and the motive to carry out the crime. Two of the passengers had been identified as al-Qaeda members and were on the FBI's terrorist-alert list prior to 9/11: Khalid al-Mihdhar and Nawaf al-Hazmi.'Watch List' Didn't Get to AirlineStatement For The Record It appears certain that all hijackers had Arab origins, and none were Afghan; moreover, both in their immense scale, careful planning and refraining from claiming responsibility, the attacks are reminiscent of al-Qaeda's previous attacks such as the 1998 US embassy bombings that killed over 200 people.
1993 World Trade Center bombing
In the World Trade Center bombing (February 26, 1993) a car bomb was detonated by Arab Islamist terrorists in the underground parking garage below Tower One of the World Trade Center in New York City. The urea nitrate-fuel oil device killed six and injured over a thousand people. It was intended to devastate the foundation of the North Tower, causing it to collapse onto its twin.
The attack was planned by a group of conspirators including Ramzi Yousef, Sheik Omar Abdel-Rahman, El Sayyid Nosair, Mahmud Abouhalima, Mohammad Salameh, Nidal Ayyad, Ahmad Ajaj, and Abdul Rahman Yasin. They received financing from al-Qaeda member Khalid Shaikh Mohammed, Yousef's uncle, who would later allegedly admit to planning the September 11 attacks.
Statements of motives prior to attacks
Starting in 1996, Osama bin Laden stated in public proclamations (fatwas) and in interviews with journalists his common list of grievances which he cited as the reason for his declaration of war against the United States.
In 1998, bin Laden and Ayman al-Zawahiri (a leader of Egyptian Islamic Jihad) co-signed a fatwa (binding religious edict) in the name of the World Islamic Front for Jihad Against Jews and Crusaders, declaring:
In an interview with journalist Rahimullah Yusufzai published in Time on January 11, 1999, Osama bin Laden was quoted as saying:
Planning the attacks According to interviews by Al Jazeera as well as United States interrogations of al-Qaeda members Ramzi bin al-Shibh and Khalid Sheikh Mohammed (captured in 2002 and 2003 respectively), Khalid Sheikh Mohammed was the instigator and prime organizer of the attacks. bin al-Shibh may have been picked as a hijacker but he failed to get into the United States.
Khalid Mohammed had provided funding to his nephew Ramzi Yousef for the World Trade Center bombing in 1993. In addition, he collaborated on Oplan Bojinka which called for ten or more airliners to be bombed in mid-air or hijacked for use as missiles. Planning for Oplan Bojinka began in 1994, and was funded in part by Osama bin Laden, but was thwarted by an accidental fire in 1995.
In mid-1996, Khalid Mohammed presented a new plan to the leadership of al-Qaeda that called for several airplanes on both east and west coasts to be hijacked and flown into targets.
According to bin al-Shibh and Khalid Mohammed, six of the hijackers played active parts in the planning, including the four who became the pilots. The other two were Khalid al-Mihdhar and Nawaf al-Hazmi. CIA operatives reportedly monitored the movements of these two known militants when they visited the US but did not notify the FBI or gain an inkling of what the hijackers were planning. However, during a 2006 Moussaoui trial cross-examination, FBI agents stated that the bureau was aware, years before the attacks in 2001, that al-Qaeda planned to use planes to destroy important buildings. Philippine Chief Superintendent Avelino Razon had noted such plans during the 1995 investigation of Oplan Bojinka, of which Razon said: