More details may emerge on the circumstances of Mashkoor’s ill-fated attempt to join ISIS, but the facts as laid out in the complaint are hallmarks of terrorism prosecutions based on FBI stings: a young man with developmental disabilities, already on the police’s radar due to mental health episodes and conflicts with family, groomed as a minor over a long period by a group of undercover FBI agents. Mashkoor’s case also follows a pattern of FBI sting operations in which a teenager is arrested shortly after their 18th birthday. As in similar cases, the court documents suggest that Mashkoor was limited...