Report of the 9/11 Commission

GENERAL FINDINGS
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 confidence is that none of the measures adopted by the U.S. government from 1998 to 2001 disturbed or even delayed the progress of the al Qaeda plot. Across the government, there were failures of imagination, policy, capabilities, and management.

Imagination
The most important failure was one of imagination. We do not believe leaders understood the gravity of the threat. The terrorist danger from Bin Ladin 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.

Al Qaeda's new brand of terrorism presented challenges to U.S. governmental institutions that they were not well-designed to meet. Though top officials all told us that they understood the danger, we believe there was uncertainty among them as to whether this was just a new and especially venomous version of the ordinary terrorist threat the United States had lived with for decades, or it was indeed radically new, posing a threat beyond any yet experienced.

As late as September 4, 2001, Richard Clarke, the White House staffer long responsible for counterterrorism policy coordination, asserted that the government had not yet made up its mind how to answer the question: "Is al Qida a big deal?"

A week later came the answer.

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