Editor’s Note: John McWhorter teaches linguistics, American studies, philosophy and music history at Columbia University and is the author of “Words on the Move.” The opinions expressed in this commentary are his own.

CNN  — 

Until recently, George Ciccariello-Maher was an anonymous political science professor at Drexel University in Philadelphia. However, of late a white-hot mob has threatened him – and his child – so gravely that he is now teaching via a video feed. This week he announced he’s resigning out of concern for his family’s safety: “My situation has become unsustainable,” he explained on his Facebook account.

Surely Ciccariello-Maher said something racist or, to use the dominant term of art, white supremacist? No – the people issuing a fountain of death threats against him all year have been from the right.

A year ago, Ciccariello-Maher tweeted a wry joke – “All I Want for Christmas is White Genocide” – in the vein of the self-critical “That’s so white” meme now popular among Blue Americans. He said the tweet was a “satirical jab at a certain paranoid racist fantasy and that white genocide does not exist.”

A few months later, he tweeted that it made him want to vomit watching someone give up their first-class airline seat to a soldier. In October, he tweeted that “Trumpism” and the “narrative of white victimization” were to blame for the lethal mass shooting in Las Vegas.

In other words, the professor’s critics now feel “injured,” by someone they thus deem unfit for human society.

Their forcing someone into hiding for just writing some stuff is unforgivable. But it should make us think about when the shoe is on the other foot.

I recently encountered someone arguing privately that protesters shouting down conservative speakers such as Charles Murray at Middlebury College earlier this year should be viewed not as menaces to free speech – given that the First Amendment does not apply at private institutions – but as simply “impolite.” The implication seemed to be that this shouting down should be permitted as an unfortunate but legitimate expression of grievance.

However, I couldn’t help wondering whether this person would feel that conservatives and skinheads shouting down liberal MSNBC host Rachel Maddow, or black radical icon Angela Davis, would qualify as merely “impolite.”

The Ciccariello-Maher episode demonstrates this hypothetical. To the people hounding the professor, there is no justifiable joking about “white genocide” – even if whites are the ones with the privilege in our society. Ciccariello-Maher’s critics also find it, we might say, impolite to disparage a soldier who is possibly about to sacrifice his life to serving his country.

Make no mistake – to go from a feeling of grievance to threatening someone, or their child (!), online is repulsive behavior. (I am eternally stunned that it is within the norms of sane human behavior to regularly send vicious messages of this kind on a whim to people who have rubbed you the wrong way.) However, there is no conception of justice or truth that makes it somehow pardonable “collateral damage” when the left behaves this way – which it does too frequently. The behaviors are mirror-image parallels.

Note, for example, the deafness to irony or abstraction in Ciccariello-Maher’s detractors. Certainly Ciccariello-Maher did not despise the innocent, hard-working soldier himself. His opposition is to America’s larger military actions. Just as certainly, a white professor – like Ciccariello-Maher – does not sincerely wish for the extinction of all people of his own race.

But anyone who understands this must also revile the equally uncomprehending, theatrical interpretation of the works of thinkers like Heather Mac Donald and Mark Lilla as “white supremacists” who, their detractors say, seek a return to the America of a century ago. Mac Donald makes arguments that police officers are not racist; Lilla suggests that to win back the White House the left should pragmatically soft-pedal identity politics in favor of stressing the economic woes of the working class in general. These arguments make some uncomfortable, but the idea that they are “Mein Kampf” in disguise is a fantasy no thoughtful person could recognize as constructive.

I suspect that many horrified by the Drexel professor’s situation will stick to a basic idea that the left is right and the right is wrong, and thus tarring and feathering the right-winger is progress while tarring and feathering the left-winger is injustice.

Yet just as many will – one hopes – understand that this view is too short-sighted, privileging the gut over the brain.

It’s easy to detect a certain performative, exaggerated essence in the onslaught against people like Ciccariello-Maher – and the exact same essence is resplendently on view in the equivalent onslaught against people like Lindsay Shepherd. Shepherd is the left-leaning graduate student pilloried by the left as transphobic for exposing students to Jordan Peterson’s argument against the use of gender-neutral pronouns, alongside arguments in favor, in order to introduce her students at Wilfrid Laurier University, in Ontario, to both sides of the controversy.

Here’s hoping that in 2018, educated American culture will open up at least somewhat more to the idea that shouting down ideas that tick you off is unsanitary behavior from anyone.