When the terrorist attacks began on September 11, 2001, numerous U.S. intelligence agencies and facilities that should have been closely following the catastrophic events taking place in the skies over America were unaware that anything was wrong. Because of their particular responsibilities and their advanced capabilities, agencies such as the FBI and the National Security Agency (NSA) should have been among the first to learn the details of the crisis. But, instead, they were apparently in an information blackout, and their knowledge of the attacks was limited to what they could learn from television reports.
The fact that key intelligence agencies and facilities experienced this problem, and all at the same time, suggests that the information blackout may have been intentional–an act of sabotage committed by the perpetrators of the attacks. Such an act could have been intended to render these agencies and facilities useless when their services were urgently needed, thereby helping to ensure that the attacks were successful.
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