You know who you are.

You cringed as you read about the attacks earlier this month on Princeton University anthropology professor Lawrence Rosen, who was denounced for using the N-word in a class on hate speech and blasphemy. Then you read that Rosen had canceled the class. And then you said, here we go again.

But only to yourself. You didn’t have the guts to go public with your concerns, either on social media or in face-to-face discussions. Why risk the vilification that Rosen received? It’s so much easier to sigh, roll your eyes and move on.

Score one for the bullies. And that’s the real subtext to the shaming of Lawrence Rosen, and of other similar episodes around the country. On questions of free speech, our campuses are deeply divided. But only one side typically speaks up, while the other keeps quiet.

Consider the controversial Brookings Institution poll from last summer, in which 51 percent of surveyed students agreed that it was acceptable for a student group to shout down a speaker “known for making offensive and hurtful statements.” That meant 49 percent disagreed, of course.

The survey is questionable, as it was opt-in, and so there's no assurance that the sample was representative. And the fraction of students who object to shouting down an offensive speaker is most likely higher than that, because the Brookings study was conducted right after the neo-Nazi rally in Charlottesville, Va. That probably skewed the results in favor of shouting down offensive speech; in normal times, we’d expect to find more students on the other side. They just don’t raise their own voices as loudly, if at all. ...