The report has shaken up the intelligence establishment

Here are the key findings of the 576-page report:

Failure to confront

The report charts how al-Qaeda was allowed to develop into a real danger to the US, concluding that while the attacks "were a shock... they should not have come as a surprise":

• "The 9/11 attack was driven by Osama Bin Laden" who "built over the course of a decade a dynamic and lethal organisation" in al-Qaeda

  The 9/11 attacks were a shock, but they should not have come as a surprise Executive summary (5.9MB) Commission report in full (7.4MB) Download the reader here

• "What we can say with confidence is that none of the measures adopted by the US government from 1998 to 2001 disturbed or even delayed the progress of the al-Qaeda plot"

• "The most important failure was one of imagination. We do not believe leaders understood the gravity of the threat"

• "At no point before 9/11 was the Department of Defense fully engaged in the mission of countering al-Qaeda, even though it was perhaps the most dangerous foreign enemy threatening the United States"

• "The FBI did not have the capability to link the collective knowledge of agents in the field to national priorities"

• "The terrorist danger from Bin Laden and al-Qaeda was not a major topic for policy debate among the public, the media or in the Congress. Indeed, it barely came up during the 2000 presidential campaign"

• No single individual was to blame, but both individuals and institutions had to take responsibility for failing to stop the attacks

• There was no operational link between al-Qaeda and ousted Iraqi President Saddam Hussein.

Missed opportunities

The report finds that the 9/11 plot might have been nipped in the bud had the security services done their work more thoroughly, although it accepts that "since the plotters were flexible and resourceful, we cannot know whether any single step or series of steps would have defeated them".

The report accuses the "organisations and systems of that time" of:

• Allowing two hijackers, Khalid al-Midhar and Nawaq Alhamzi, to enter and move about the US without proper surveillance despite their known links to al-Qaeda

• "Not linking the arrest of Zacarias Moussaoui, described as interested in flight training for the purpose of using an airplane in a terrorist act, to the heightened indications of attack"

• Not discovering false statements on visa applications and not recognising faked passports

• Not expanding no-fly lists to include names from terrorist watch lists and not searching airline passengers identified by computer-based screening

• Not hardening aircraft cockpit doors or taking other measures to prepare for the possibility of suicide hijackings

Open to attack

While praising the response of members of the emergency services to the attacks, the report finds institutional weaknesses within the US which both made it easier for extremists to attack and harder for the authorities to respond adequately:

• "The hijackers had to beat only one layer of security - the security checkpoint process... Once on board, the hijackers were faced with aircraft personnel who were trained to be non-confrontational in the event of a hijacking"

• "The civilian and military defenders of the nation's airspace... attempted and failed to improvise an effective homeland defence against an unprecedented challenge"

• "The chain of command did not function well. The president could not reach some senior officials. The secretary of defence did not enter the chain of command until the morning's key events were over"

Key recommendations

The report says that America is a safer place since the attacks, after action by the Bush administration.

"Because of offensive actions against al-Qaeda since 9/11, and defence actions to improve homeland security, we believe we are safer today," it notes.

However, it warns against complacency and makes detailed recommendations :

• To create a national counter-terrorism centre "unifying strategic intelligence and operational planning against Islamist terrorists across the foreign and the domestic divide"

• To appoint a new Senate-confirmed national intelligence director to unify the intelligence community of more than dozen agencies

• To create a "network-based information sharing system that transcends traditional governmental boundaries"

• To set up a specialised and integrated national security unit within the FBI; the report did not support creation of a new domestic intelligence agency

• To strengthen Congressional oversight

• To strengthen the FBI and Homeland defenders

• To develop global strategy of diplomacy and public relations to dismantle Osama Bin Laden's al-Qaeda terror network and defeat its militant Islamic ideology

• To establish a better dialogue between the West and the Islamic world