Cesar Sayoc was arrested by federal authorities in Florida on Friday morning and charged with crimes related to sending 13 apparently homemade pipe bombs to high-profile Democrats. None of them detonated, but the FBI says the bombs indeed contained explosive material. Sayoc may well have meant to kill George Soros, Hillary Clinton, Barack Obama, Cory Booker, and others. Sayoc does not appear to be severely mentally ill, like other perpetrators of high-profile crimes in our country in recent years, but he is a kooky and fringe character. He sports a long and bizarre arrest record, one of the reasons authorities...