On Saturday afternoon, shortly before her camera captured a car plowing through left-wing activists in Charlottesville, killing one and injuring more than a dozen others, Faith Goldy warned that the left was spinning out of control. “Hundreds and hundreds of antifa, weird BLM, idiots dressed like clowns,” said Goldy, a reporter for the Canadian alt-right news site The Rebel. “This is okay, as long as you’re not the alt-right. The alt-right wasn’t allowed to demonstrate any show of force.” As if on cue, activists began chanting “black lives matter” in the background of Goldy’s shot. “Chant BLM, and all of...