Cain Clark, 17, and Caleb Velasquez, 18, attacked the Islamic Center of San Diego, killed 3 people, then killed themselves. They live-streamed the whole thing. This is the third major shooting targeting a religious community in recent weeks. At this point the pattern is undeniable: conspiracy theories are radicalizing American kids into murderers, and we keep treating each attack as an isolated incident instead of a systemic failure.