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.
Mohamed Atta
Mohamed Mohamed el-Amir Awad el-Sayed Atta ( ; ""  ; September 1, 1968 – September 11, 2001) was an Egyptian hijacker and one of the ringleaders of the September 11 attacks in which four United States commercial aircraft were commandeered with the intention of destroying specific civilian targets. He served as the hijacker-pilot of American Airlines Flight 11 and crashed the plane into the North Tower of the World Trade Center as part of the coordinated attacks. At 33 years of age, he was the oldest of the 19 hijackers who took part in the attacks.