On Thursday night, leftist protesters at a Donald Trump rally in San Jose, California, chased down Donald Trump supporters and beat them bloody, spit in their faces, pelted a female Trump supporter with eggs, hurled rocks at police horses, and broke down metal barriers – all while burning American flags and screaming slogans like “America Was Never Great!” and “Make America Mexico Again!”

In recent years, under the tender tutelage of the Obama Department of Justice, mass violent action by leftists has become commonplace across the country, from the Occupy Wall Street movement to Black Lives Matter-inspired mob violence in Ferguson and Baltimore, from campus chaos at California State University of Los Angeles to this sort of violence at Trump rallies.

The tendency of the media has been, however, to blame the rise of Donald Trump for this violence. They blame Trump’s rhetoric for eliciting violent response from the left – a pure example of “she was wearing a short skirt, so the rape was inevitable” logic. To make that logic perfectly clear, Tuscon sportscaster Jacob Rascon Paul Cicala tweeted, “Hey brother…you aren’t reporting that she was taunting protesters moments before pointing to her Trump shirt etc. Please be fair…not ok my friendthose protesters are definitely wrong. But, she has to be careful egging them on or she sets herself up for that.” Vox editor Emmett Rensin tweeted, “Advice: If Trump comes to your town, start a riot.” He then added, “Listen, if Trump is Hitler then you’ve got no business condemning rioters. If he isn’t, you’ve got no businesses pretending normal is better.” The Mayor of San Jose, Democrat Sam Liccardo, blamed Trump directly: “At some point Donald Trump needs to take responsibility for the irresponsible behavior of his campaign.” It is worth noting that there were many reports of San Jose police standing down as Trump supporters were attacked.

This is wildly dishonest. It’s actually despicable.

Here are three rules regarding political violence.

1. Violence In Response To Political Differences Is Totally Unacceptable. Why has this become controversial? Because the left determined in the last several years that certain speech is so terrible that it must be curbed either by official or unofficial violence. Hence the term “microaggression,” which has become so popular on college campuses: the implication of the term itself is that speech you don’t like is a form of aggression to be met with actual aggression. Violence is only an acceptable response to actual violence, not speech. But the left doesn’t believe that. So they’ll either send the guy with the government gun to shut down speech they don’t like, or punch those who express sentiments they don’t appreciate.

2. Politicians Who Egg On Violence Are At Least Partially Responsible For Their Supporters’ Violence. President Obama has backed violence by lending credence to the Black Lives Matter movement, even as they promote riots. Deray Mckesson, a leader of BLM, has openly justified riots and looting (and then been handed the keys to the Twitter car). The left thinks that riots are fine, so long as they’re the ones doing the rioting.

The same is true for Trump himself: he’s talked openly and glowingly of possible convention riots; he’s said he’d like to “punch” a protester “in the face, I tell ya”; he’s said that a protester “should have been roughed up”; he’s pined for the “old days” when protesters would be “carried out on a stretcher, folks”; he’s said he would look into paying the legal bills of a rallygoer who cold-cocked a protester.

3. Politicians Are NOT Responsible For Violence Against Them. Trump’s responsibility for protester violence extends only to people he tells to engage in violence. He is not responsible for a so-called “climate of violence.” Nobody is responsible for inciting violence against themselves. That’s just nonsensical. Which is why Bernie Sanders and Hillary Clinton and Barack Obama should immediately condemn violence against Trump supporters, just as Trump has been asked repeatedly about condemning violence by his supporters. It is worth noting that Trump supporters getting violent with anti-Trump protesters are occasional and rare – there have been no pro-Trump riots. Rioting mobs are reserved for the left.

The left has embraced political violence ever since Barack Obama assumed office; Trump’s campaign, being fully reactionary, has done the same, though its effect has been smaller since conservatives by nature don’t believe in political violence to the same degree as the left. All of this is leading to a mainstreaming of political violence not seen since the 1960s.

Grab your riot gear, folks. Things are about to get ugly.