Terrorists Deliver Their Message With Lethal Simplicity - The New York Times
WASHINGTON — In the months after the Sept. 11, 2001, terrorist attacks, Western officials worried about additional attacks, possibly using weapons of mass destruction, that could kill thousands. The United States invested heavily in biological and nuclear detectors and other high-tech gear. Jihadist terrorism seemed a menace that would unnerve entire countries and might last for a generation.
More than a decade and a half later, the threat and fear have proved real and lasting.