Report of the 9/11 Commission

Capabilities
Before 9/11, the United States tried to solve the al Qaeda problem with the capabilities it had used in the last stages of the Cold War and its immediate aftermath. These capabilities were insufficient. Little was done to expand or reform them.

The CIA had minimal capacity to conduct paramilitary operations with its own personnel, and it did not seek a large-scale expansion of these capabilities before 9/11. The CIA also needed to improve its capability to collect intelligence from human agents.

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

America's homeland defenders faced outward. NORAD itself was barely able to retain any alert bases at all. Its planning scenarios occasionally considered the danger of hijacked aircraft being guided to American targets, but only aircraft that were coming from overseas.

The most serious weaknesses in agency capabilities were in the domestic arena. The FBI did not have the capability to link the collective knowledge of agents in the field to national priorities. Other domestic agencies deferred to the FBI.

FAA capabilities were weak. Any serious examination of the possibility of a suicide hijacking could have suggested changes to fix glaring vulnerabilities-expanding no-fly lists, searching passengers identified by the CAPPS screening system, deploying federal air marshals domestically, hardening cockpit doors, alerting air crews to a different kind of hijacking possibility than they had been trained to expect. Yet the FAA did not adjust either its own training or training with NORAD to take account of threats other than those experienced in the past.