Stochastic Terrorism n. Acts of violence by random extremists, triggered by political demagoguery. When President Trump tweeted a video of himself body-slamming the CNN logo in 2017, most ­people took it as a stupid joke. For Cesar Sayoc, it may have been a call to arms: Last October the avowed Trump fan allegedly mailed a pipe bomb to CNN headquarters. No one told Sayoc to do it, but the fact that it happened was really no surprise.

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