The destruction of the twin towers of the World Trade Center and the attack on the Pentagon -- all within one hour on September 11, 2001 -- demonstrated America's shocking vulnerability to terrorism. Yet terror had already emerged on America's shores eight years earlier, when the mysterious terrorist mastermind, Ramzi Yousef (arrested after a botched attempt to down a dozen U.S. airlines) bombed the World Trade Center in an attempt to fell the buildings. His attacks were viewed as the harbinger of a new terrorism, carried out by an elusive enemy driven by religious fanaticism to unprecedented hatred of the United States.