An NYU professor crusading against political correctness and student coddling was booted from the classroom last week after his colleagues complained about his “incivility,” The Post has learned.

Liberal studies prof Michael Rectenwald, 57, said he was forced Wednesday to go on paid leave for the rest of the semester.

“They are actually pushing me out the door for having a different perspective,” the academic told The Post.

Rectenwald launched an undercover Twitter account called Deplorable NYU Prof on Sept. 12 to argue against campus trends like “safe spaces,” “trigger warnings” policing Halloween costumes and other aspects of academia’s growing PC culture.

He chose to be anonymous, he explained in one of his first tweets, because he was afraid “the PC Gestapo would ruin me” if he put his name ­behind his conservative ideas on the famously liberal campus.

“I remember once on my Facebook I posted a story about a kid who changed his pronoun to ‘His Majesty’ because I thought it was funny,” he told The Post. “Then I got viciously attacked by 400 people. This whole milieu is nauseating. I grew tired of it, so I made the account.”

On Oct. 11, Rectenwald used his ­internet alter ego to criticize “safe spaces” — the recent campus trend of “protecting” students from uncomfortable speech — as “at once a hall of mirrors and a rubber room.”

Two weeks ago he posted on his “anti-PC” feed a photo of a flyer put out by NYU resident advisers telling students how to avoid wearing potentially offensive Halloween costumes.

His caption read: “The scariest thing about Halloween today is . . . the liberal totalitarian costume surveillance. NYU RAs gone mad,” he wrote.

“It’s an alarming curtailment of free expression to the point where you can’t even pretend to be something without authorities coming down on you in the universities,” Rectenwald told The Post.

But the Twitter feed soon sparked a “witch hunt” by the growing army of “social justice warriors,” he said.

In an interview published Monday in the Washington Square News, NYU’s Independent Student Newspaper, the eight-year instructor admitted he was the Deplorable NYU Prof.

“My contention is that trigger warning, safe spaces and bias hot-line reporting is not politically correct. It is insane,” he told the student paper. “The crazier and crazier that this left gets . . . the more the alt-right is going to be laughing their asses off [and] getting more pissed.”, he was quoted as saying.

The divorced father of three came forward because “I thought there was nothing objectionable about what I had said.”

But Rectenwald says he began getting “dirty looks” in his department and on Wednesday figured out why: A 12-person committee calling itself the Liberal Studies Diversity, Equity and Inclusion Working Group, including two deans, published a letter to the editor in the same paper.

‘Academic freedom: It’s great, as long as you don’t use it.’ - Michael Rectenwald

“As long as he airs his views with so little appeal to evidence and civility, we must find him guilty of illogic and incivility in a community that predicates its work in great part on rational thought and the civil exchange of ideas,” they wrote of the untenured assistant professor.

“We seek to create a dynamic community that values full participation. Such efforts are not the ‘destruction of academic integrity’ Professor Rectenwald suggests, but rather what make possible our program’s approach to global studies,” they argued. Rectenwald likened the attack to “a Salem witch trial. They took my views personally. I never even mentioned them and I never even said NYU liberal studies program. I was talking about academia at large,” said the professor, a popular instructor who was graded 4.4 out of 5 on ratemyprofessors.com.

The same day the letter was published, Rectenwald was summoned to a meeting with his department dean and an HR representative, he says.

“They claimed they were worried about me and a couple people had expressed concern about my mental health. They suggested my voicing these opinions was a cry for help,” Rectenwald told The Post. “Then they said I should leave and get help.”

He said, “They had no reason to believe that my mental health was in question, unless to have a different opinion makes one insane.”

Students told him that professors openly discussed with students how he may be fired.

The leave has “absolutely zero to do with his Twitter account or his opinions on issues of the day,” said NYU spokesman Matt Nagel.

But Rectenwald is disheartened.

“I’m afraid my academic career is over,” he said Rectenwald. “Academic freedom: It’s great, as long as you don’t use it.”