Anthony Shaffer , a former DIA officer , has claimed that DIA was aware of and failed to adequately act against one of the organizers of the September 11 attacks prior to the event , in what became known as the Able Danger controversy . Shaffer 's claims were rejected and later his security clearance revoked , with the Pentagon denying any wrongdoing . Later Shaffer published his book Operation Dark Heart but , upon complaints from DIA and NSA that it included national security information , the Defense Department went as far as to buy and destroy the initial 10,000 copies of the book , causing the Streisand effect
September 11 attacks
September 11 attacks
Defense Intelligence Agency