This In-Depth report from our International Security Program examines broad trends in the jihadist terrorist threat facing the United States that have emerged since the 9/11 attacks. We provide an overview of the terrorism in cases we’ve tracked since 9/11, and we examine three key questions: Who are the terrorists targeting the United States? Why do they engage in terrorism in the first place? And what threat do they pose?
The data in this report consists of individuals accused of jihadist terrorism related crimes since 9/11 who are either American citizens or who engaged in jihadist activity within the United States. The data also include a small number of individuals who died before being charged but were widely reported to have engaged in jihadist criminal activity, We define jihadists to include those who are motivated by versions of bin Laden’s global ideology or otherwise provide support to groups that follow a version of that ideology. We exclude cases linked to Hamas, Hezbollah, and similar groups that do not follow bin Laden’s ideology and do not target the United States.