The 567-page report by the National Commission on Terrorist Attacks Upon the United States calls this approach a "failure of imagination" by the Central Intelligence Agency (CIA) and the Federal Bureau of Investigation (FBI). It also blamed Congress, saying it did not provide adequate oversight of the CIA and FBI.
Ultimately, the commission concluded that the attacks may have come as a shock to the nation, but should not have been a surprise, if the government had grasped the gravity of the threat.
The panel's chairman, Thomas Kean, put it this way: "We were unprepared. We did not grasp the magnitude of a threat that had been gathering over a considerable period of time. As we detail in our report, this was a failure of policy, management, capability, and, above all, a failure of imagination."
But the 10-member, bi-partisan panel did not fault either Bush or Clinton. It also said it found no collaboration between Al-Qaeda and the government of Iraq, even though Bush cited this possibility as a reason to go to war in Iraq last year.
The report recommends the establishment of a national counterterrorism center led by a director who would have authority over all the nation's intelligence agencies, including the CIA and FBI and the Defense Intelligence Agency. It also calls for stronger Congressional oversight, but not for a domestic spy agency.
Kean and his vice chairman, Lee Hamilton, gave Bush a copy of the report at the White House. Bush thanked them, and said: "They've done a really good job of learning about our country, learning about what went wrong prior to September 11th and making very solid, sound recommendations about how to move forward. I assured them that where government needs to act, we will."
The commission's report said U.S. authorities had several opportunities to stop the Al-Qaeda hijackers. For example, it cited inept efforts to capture or kill Osama bin Laden, Al-Qaeda's founder.
Further, it said Zacarias Moussaoui, one of the men believed to have been an active part of the plot, was arrested a month before the attacks, but the FBI did not link his interest in flying passenger jets with an impending attack.
In short, Kean said, the U.S. government simply was unable to prevent the attacks. "Now, we recognize, as commissioners, that we have the benefit of hindsight and since the plotters were flexible and resourceful, we cannot know whether any single step or series of steps would have defeated them. What we can say with a good deal of confidence is that none of the measures adopted by the United States government before 9/11 disturbed or even delayed the progress of the Al-Qaeda plot," Kean said.
Also, U.S. television on 22 July broadcast surveillance video tapes from the Washington airport that five of the hijackers used to commandeer the plane that crashed into the Pentagon. The tapes show four of the men triggering metal-detector alarms, then quickly being permitted to board the plane that they would turn into a guided missile.
In part, the panel attributed such problems to an intelligence apparatus that had not adapted its operations since the days when the Soviet Union was viewed as the greatest threat to America.
Meanwhile, it said, bin Laden had founded Al-Qaeda, and was changing it rapidly to confound outside interference. The report also concluded that bin Laden's operatives quickly learned and effectively exploited weaknesses in U.S. airline and border security.
The report said that in confronting groups like Al-Qaeda, the U.S. government relied too much on diplomatic maneuvers and not enough on effective military options.