Donald Rumsfeld
The United States was attacked on September 11, 2001 by al Qaeda terrorists who hijacked commercial airliners and crashed them in coordinated strikes into both towers of the World Trade Center in Lower Manhattan, New York City and the Pentagon in Washington, D.C. The fourth plane crashed into a field in Shanksville, Pennsylvania, and its target was likely a prominent building in Washington, D.C., most probably either the Capitol Building or the White House. Within three hours of the start of the first hijacking and two hours after American Airlines Flight 11 struck the World Trade Center, Rumsfeld raised the defense condition signaling of the United States offensive readiness to DEFCON 3, the highest it had been since the Arab-Israeli war in 1973.
September 11 attacks advance-knowledge conspiracy theories
There have also been allegations that the hijackers' preparations may have been given assistance by U.S. intelligence. According to CBS News, "two of the Sept. 11 hijackers who lived in San Diego in 2000 rented a room from a man who reportedly worked as an undercover FBI informant... the FBI informant prayed with them and even helped one open a bank account." Doubts have been raised about the speed with which the hijackers were identified, leading to suggestions that the FBI already had the names of the hijackers in advance. In his book "Against All Enemies", Richard Clarke said that at 9:59 am on September 11, which is the time when WTC2 collapsed and 8 minutes before NORAD even knew Flight 93 had been hijacked, the FBI already had a list of the 19 alleged hijackers. A former high-level intelligence official said that "Whatever trail was left was left deliberately—for the F.B.I. to chase."