The FAA, NORAD and the military have cooperative procedures by which fighter jets automatically intercept commercial aircraft under emergency conditions. These procedures were not followed.
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U.S. air safety and air defense emergency systems are activated in response to problems every day. On 9-11 they failed despite, not because of, the extreme nature of the emergency. This could only happen if individuals in high positions worked in a coordinated way to make them fail.

GUILTY FOR 9-11: BUSH, RUMSFELD, MYERS