Taking terrorism on the road: American ISIS supporters and the decision whether to travel or stay home

A report on the decision to travel versus act in the homeland among ISIS-inspired persons living in the United States.

Implications

ISIS-inspired and enabled individuals in the United States continue to pursue dual mobilization pathways: attempting to travel abroad and plotting attacks at home. We note that, even after the collapse of the caliphate, roughly one-third of post-2019 defendants sought to travel. At the same time, the ISIS threat has clearly not shifted exclusively in one direction. Recent cases—including the January 2025 New Orleans attack—demonstrate that individuals who remain in the United States can and do operationalize violence locally in support of ISIS. Taken together, the evidence points to a persistent dual-threat dynamic rather than a substitution effect between travel and homeland attack activity.

Distributions During Phases of the Caliphate

Full Report