These people don't represent "the Left." They represent a marginal subset, the "illiberal Left," or are simply anarchists.

Lefties aren't afraid of anybody's speech. But we disapprove of bigots and hate-mongerers. As I said elsewhere, I wish anti-alt right agitators would simply ignore Milo and other professional trolls. They are giving him what he wants.

Most lefties/libs insist on non-violent protest like the Women's March on Washington. Half a million and not one arrest.