The terrorist attacks of 9/11 plunged the United States into a determined counteroffensive against Osama bin Laden and his al Qaeda terrorist network. This report details the initial U.S. military response to those attacks, namely, the destruction of al Qaeda_s terrorist infrastructure and the removal of the ruling Taliban regime in Afghanistan. The author emphasizes several distinctive achievements in this war, including the use of precision air-delivered weapons that were effective irrespective of weather, the first combat use of Predator unmanned aerial vehicles armed with Hellfire missiles, and the integrated employment of high-altitude drones and other air- and space-based sensors that gave CENTCOM unprecedented round-the-clock awareness of enemy activity.