Jonathan Gilliam, a former FBI agent, Navy SEAL, and U.S. Air Marshal, uses Iran-backed proxy groups as an example of how terrorism has evolved from big attacks to social media influencing. “My fear is not just that there are sleeper cells in and around, but that they are inspiring many of these Americans that are not Muslim to go out and do these things,” he says. Gilliam advises the FBI to think outside the box in order to address the growing domestic threat.