What do we know about ISIS? Who are they, and how do they make money and recruit fighters — and wives? On Nov. 6, WGBH hosted a public panel discussion, led by PRI The World’s Aaron Schachter, to answer some of those questions. Participants included FRONTLINE's Martin Smith, who discussed his recent film “The Rise of ISIS,” Professor Mia Bloom of the UMASS Lowell Center for Terrorism and Security Studies, and Charles Sennott, a veteran foreign reporter who founded the GroundTruth Project to train a new generation of foreign correspondents.