This was the alt-right’s favorite chat app. Then came Charlottesville.
They posted swastikas and praised Hitler in chat rooms with names like "National Socialist Army" and "Führer's Gas Chamber." They organized last weekend's "Unite the Right" rally in Charlottesville, Va., connecting several major white supremacy groups for an intimidating display of force. And when that rally turned deadly, with the killing of a 32-year-old...