Terrorism has emerged as one of the central global threats of the twenty-first century. Terrorism is a strategy by which subnational groups, not recognized as legitimate by the states they oppose, seek to resist those states by targeting nonstate actors, disrupting the flow of everyday life, and spreading generalized fear among the populations of those states. Terrorism has a long history, but it is primarily associated with the rise of colonialism. The rise in terrorism since 2000 is linked to a number of factors. Another key area of global interconnectedness in which international terrorism plays a significant role is drug trafficking. State terrorism should not be confused with state-sponsored terrorism, in which a state harbors, and sometimes supports, the terrorist enemies of another state. Terrorism, however, is not an inherently religious act, nor is Islam, or any other religion, especially prone to producing terrorists.