While researchers began to assemble open source terrorism event data bases in the late 1960s, until recently most of these data bases excluded domestic attacks. This could be a particularly misleading exclusion for the United States because the United States is often perceived to be a central target of transnational terrorism. We began the research on which this essay is based with 53 foreign terrorist groups that have been identified by U.S. State Department and other government sources as posing a special threat to the United States (LaFree, Yang, Crenshaw, 2009). Using newly available terrorist attacks, we examined 16,916 attacks attributed to these foreign groups between 1970 and 2004. We found that just over three percent of attacks by these designated anti-U.S. groups were actually directed at the United States. Moreover, 99 percent of the attacks that targeted the United States did not occur on U.S. soil, but were aimed at U.S. targets in other countires (e.g., embassies or multilateral corporations). We also found that over 90 percent of the non-U.S. attacks were domestic (nationals from one country attacking targets of the same nationality in the same country).
LaFree, Gary, and Sue-Ming Yang. 2009. "International Cooperation, Not Unilateral Policies May Be the Best Counterterrorism Strategy." In Contemporary Issues in Criminal Justice Policy, eds. Natasha A. Front, Joshua D. Freilich, and Todd R. Clear. Belmont, CA:Wadsworth. 121-128.