It's easy to recognize the light of true emuna as opposed to the dark-side faith that fuels fanaticism and terrorism. The light side builds and heals. The dark side destroys and kills. Even if someone has a beard and sidecurls, yet throws a rock at a policeman or soldier, he's no better than a suicide bomber from ISIS, for both are playing for the dark-side team.
Our task is to be a "Light unto the Nations," spreading the light of emuna to every human being on earth. Each one of us must be an ambassador of emuna by living our lives in integrity and in respect for every human. This differentiates us from the murderous Jihadis and shahidis (Arabic for "holy warriors" [sic] and "suicide bombers"). May the martyred souls of the 9/11 victims rest in eternal bliss.