Ahead of Ben Shapiro‘s highly-anticipated speech at UC Berkeley, Tucker Carlson took on an Antifa activist on the subject of free speech.

Mike Isaacson — an Antifa backer who is also a professor at John Jay College of Criminal Justice — stated his belief that “communities have the right to defend themselves against groups that actively seek to eliminate members of that community.”

“Defend themselves against violence?” Carlson asked.

“Yes, against violence.” Isaacson replied.

After the Fox News host tried to push back, Isaacson mockingly asked if we’re “going to pretend” that violent racists like Dylann Roof didn’t exist.

“Are you really a professor, by the way?” Carlson shot back.

Carlson asked for an example for a public figure who should have their free speech “taken away,” Isaacson invoked alt-right leader Richard Spencer and called him a “danger to society.”

“When he speaks in public, what he is doing- he is publicly recruiting people to his very violent movement, very violent ideology,” Isaacson said.

When pressed by Carlson if he thought Spencer “had the right to speak in public,” Isaacson said he doesn’t think Spencer has a right to speak in public “unopposed.”

“But it’s not opposition,” Carlson responded. “You shut people down, you prevent people from speaking, you commit violence against them.”

Carlson asked if all of that was justified, Isaacson said “yes.”

“I believe communities have the right to defend themselves against threats to their communities,” Isaacson reiterated.

“Against ideas they don’t like!” Carlson said.

Carlson accused the Antifa activist of “blurring the lines” between protesting and preventing people they don’t agree with from speaking.

While the exchange was heated, Isaacson was clearly no match for Carlson. Dave Weigel of the Washington Post said it best.

The term for this in boxing is “tomato cans” https://t.co/u9fRrM0Jdu — Dave Weigel (@daveweigel) September 15, 2017

Watch the clip above, via Fox News.

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