The 9/11 attacks were part of Al Qaeda's strategy to
disrupt Western economies and impose both direct and secondary costs on the United States and
other nations. The immediate costs were the physical damage, loss of lives and earnings, slower
world economic growth, and capital losses on stock markets. Indirect costs include higher insurance
and shipping fees, diversion of time and resources away from enhancing productivity to protecting
and insuring property, public loss of confidence, and reduced demand for travel and tourism. In a
broader sense, the 9/11 attacks led to the invasions and occupations of Afghanistan and Iraq (and the
Global War on Terrorism) and perhaps emboldened terrorists to attack in Bali, Spain, Morocco, and
Saudi Arabia. A policy question for Congress is how to evaluate the costs and benefits of further
spending to counter terrorism and its economic impact. This report will be updated periodically.