No one definition of terrorism has gained universal acceptance. For the purposes of this report, however, we have chosen the definition of terrorism contained in Title 22 of the United States Code, Section 2656f(d). That statute contains the following definitions:
The term terrorism means premeditated, politically motivated violence perpetrated against noncombatant1 targets by subnational groups or clandestine agents, usually intended to influence an audience.
The term terrorist group means any group practicing, or that has significant subgroups that practice, international terrorism.
The US Government has employed this definition of terrorism for statistical and analytical purposes since 1983.
Domestic terrorism is probably a more widespread phenomenon than international terrorism. Because international terrorism has a direct impact on US interests, it is the primary focus of this report. However, the report also describes, but does not provide statistics on, significant developments in domestic terrorism.