Terry v. Ohio’s “reasonable suspicion” test was created in the context of domestic law enforcement, but it did not remain there. This Essay examines the effect of transplanting this test into a new context: the world of terrorist watchlists. In this new context, reasonable suspicion is the standard used to authorize the infringement on liberty that often results from being watchlisted. But nothing else from the case that created that standard remains the same. The government official changes from a local police officer to an anonymous member of the intelligence community. The purpose changes from crime prevention to counterterrorism. The technology changes from a police officer’s notebook or filed report to a massive and remote computer databank. And, most significantly, the person who determines whether the reasonable suspicion standard has been met changes from a neutral and detached magistrate to the executive official who harbored the suspicion in the first place.