On Friday night in Chicago, violence broke out between supporters and protesters at a Donald Trump rally, leading Trump to cancel the event. On Saturday, Trump blamed the protesters and "thugs" — a racially coded word — for the violence.

But maybe Trump should blame himself. As Rachel Maddow demonstrated in a string of clips aired on MSNBC, Trump has consistently called for violence against protesters at his rallies.

Here are Trump's previous comments in response to demonstrators at his events, taken from Maddow's video (starting at 3:40):

February 1 in Iowa: "If you see somebody getting ready to throw a tomato, knock the crap out of them, would you? Seriously. Okay? Just knock the hell. I promise you I will pay for the legal fees. I promise."

February 22 in Nevada: "I love the old days. You know what they used to do to guys like that when they were in a place like this? They'd be carried out on a stretcher, folks. It's true. … I'd like to punch him in the face, I'll tell you."

February 26 in Oklahoma: "In the good old days, they'd rip him out of that seat so fast. But today, everybody's politically correct. Our country's going to hell with being politically correct."

February 29 in Virginia: "Get him out of here please. Get him out. Get him out. … Are you from Mexico? Are you from Mexico? Huh? Are you from Mexico?"

March 4 in Michigan: "Get out of here. Get out. Out! … This is amazing. So much fun. I love it. I love it. We having a good time? USA, USA, USA! … All right, get him out. Try not to hurt him. If you do, I'll defend you in court. Don't worry about it. … We had four guys, they jumped on him, they were swinging and swinging. The next day, we got killed in the press — that we were too rough. Give me a break. You know? Right? We don't want to be too politically correct anymore. Right, folks?"

March 4 in Michigan: "Remember when Bernie Sanders, they took the mic away from him? That's not going to happen with us, folks. That's not going to happen. Remember that? He walked away from the mic and he stood back and he watched these two young girls talking to the audience. And they said, 'We came to listen to him!' And he was standing in the back as two women took the mic away. No, that doesn't happen to us. Get that guy out of here! Get him out! Get that guy out of here!"

March 9 in North Carolina: "We had some people, some rough guys like we have right in here. And they started punching back. It was a beautiful thing. I mean, they started punching back. … In the good old days, this doesn't happen because they used to treat them very, very rough. And when they protested once, you know, they would not do it again so easily. But today, they walk in and they put their hand up and put the wrong finger in the air at everybody, and they get away with murder, because we've become weak."

March 11 in Missouri, hours before the Chicago rally: "Part of the problem and part of the reason it takes so long is nobody wants to hurt each other anymore. Right? And they're being politically correct the way they take them out. So it takes a little bit longer. And honestly, protesters, they realize it — they realize that there are no consequences to protesting anymore. There used to be consequences. There are none anymore."

Trump's message in all these incidents is clear: Supporters should rough up protesters. Friday night's chaos seems like a natural reflection of that.

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