In late June, in Portland Ore., marchers gathered for a rally billed as the Patriot Prayer. The event, organized by a man named Joey Gibson, was intended to be a quiet afternoon of reflection on the state of the nation. Then antifa slithered in. The far-left domestic terrorist organization preceded their appearance by threatening violence against whoever showed up. The afternoon descended into a bloody rumble in the streets. It was declared a riot, and police were told to stand down. Video footage shows the moment the conflict began, with a sea of masked, black-cl…