There is no known cure for terrorism, but we know how the disease takes hold. Recruitment takes place via social network or via face-to face indoctrination. Fanatic clergy like Imam Shahin and Mahmoud Harmoush, who delivered a similar screed in Riverside, California on the same day, play an outsize role inciting true believers against enemies. It’s not just about Jews and synagogues. Massacres of tourists in London, concertgoers in Manchester, Christian clergy in Normandy, innocents in Paris, Brussels, and San Bernadino, prove that jihadists see enemies everywhere.