Protesters at recent Donald Trump campaign rallies have made almost as much news as the presidential candidate himself — getting sucker-punched, landing sucker punches, stopping traffic, stopping the rallies, claiming they were banned from the events. Brandon Tatum, an officer in the Tucson Police Department, went to a Trump rally on Saturday as a civilian to see what was going on. In a subsequent video, he said he thought there was going to be “a full-fledged riot” at the event — but not because of Trump’s supporters. The protesters were the problem, Tatum said. “These people were acting so outrageous,”...