A day after Rumsfeld announced that the Department of Defense could not account for about $2.3 trillion worth of transactions, al-Qaeda terrorists 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.

Rumsfeld addressed the nation in a press conference at the Pentagon, just eight hours after the September 11 attacks and stated, "It's an indication that the United States government is functioning in the face of this terrible act against our country.
I should add that the briefing here is taking place in the Pentagon.
The Pentagon's functioning.
It will be in business tomorrow."
A day after Rumsfeld announced that the Department of Defense could not account for about $2.3 trillion worth of transactions, al-Qaeda terrorists 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.
Rumsfeld addressed the nation in a press conference at the Pentagon, just eight hours after the September 11 attacks and stated, "It's an indication that the United States government is functioning in the face of this terrible act against our country. I should add that the briefing here is taking place in the Pentagon. The Pentagon's functioning. It will be in business tomorrow."
Donald Rumsfeld