Vice published a story yesterday titled “Extremism experts are starting to worry about the left.” My reaction: It’s about damn time.

Levin, a former New York City cop who studies domestic extremism as the director of the Center for the Study of Hate and Extremism at California State University, was documenting a Klan rally in Anaheim, California, when a counterprotest suddenly took a violent swing — forcing Levin to physically place himself between a Klansman and a furious, anti-fascist mob that seemed ready to kill…

“I think we’re in a time when we can’t ignore the extremism from the Left,” said Oren Segal, the director of the Center on Extremism, an arm of the Anti-Defamation League. Over the past few months, the ADL, which hosts regular seminars on homegrown extremism for law enforcement officials, has begun warning of the rising threat posed by far-left groups, most recently at a seminar just this past Sunday. “When we have anti-fascist counterprotests — not that they are the same as white supremacists — that can ratchet up the violence at these events, and it means we can see people who are violent on their own be attracted to that,” Segal said. “I hate to say it, but it feels inevitable.”…

Levin is worried about it too: The embrace by the far left of tactics that were previously the purview of the far right means the level of political tension in the country can only go up. “I’ve been going up and down the state of California meeting with law enforcement officials about this. I’m very concerned about it,” he said. “What we’re seeing is the democratization of extremism and the tactics of radicalism. I’ve been warning about this, and nobody gave a shit.”

Somewhere in the middle of the article, Vice points out that violence is nothing new on the far left. In the 1960s groups like the Weather Underground ran domestic terror campaigns. That history seems relevant in light of the two shootings of police officers—one in Dallas and one in Baton Rouge—by black radicals last year. The Baton Rouge shooter was a black separatist who apparently admired Huey Newton. The shooter also praised the actions of Dallas shooter Micah Xavier Johnson. Johnson was a fan of a litany of far-left extremist groups who wanted to kill white police officers.

Those are two significant examples involving loss of life. Earlier today the Daily Caller published a list of left-wing attacks on conservatives which contains 35 bullet points, all of them since last July. While those attacks don’t involve deaths they do involve plenty of physical violence and some death threats. And the list is far from complete. It doesn’t include this melee which took place in Huntington Beach in March after an Antifa member pepper sprayed a pro-Trump marcher. The list also doesn’t include the left-wing protester who fired a gun at police during a Dakota Access Pipeline protest.

And there seem to be plenty of people on the left spurring others on to this kind of violence. In January I wrote about a Black Lives Matter protester who gave a speech saying “we need to stark killing people.” Seven years ago, progressive cartoonist published a book whose premise was that violent revolution (by the left) was necessary. So, yes, I think it’s past time to start taking a hard look at left-wing violence and those who encourage it.