Some of the most potent threats to free speech these days come not from our government or corporations, but from our citizenry. Pitched battles being waged at Yale and the University of Missouri pit speech versus speech in a contest of who and what is entitled to be heard. These are only the latest examples: In recent years speakers have been disinvited, campus events disrupted and activists threatened for speaking their minds.

The passions are authentic and the debates matter. But proponents of social and racial justice and free speech advocates are talking past one another, fueling mutual frustrations. Rather than a casualty of the drive to counter racism on campus, the defense of free speech is essential to it.

Simmering racial tensions at Yale combusted when the question of what constitutes a legitimate Halloween costume — and who gets to decide — escalated into a war of emails and videos endangering the reputations and safety of two college masters accused of insensitivity, and a student whose fiery tirade against one of them has been met with death threats online.

At the University of Missouri, after protests forced the school’s president and chancellor to resign over problems of campus racism, a student journalist was browbeaten; his entreaty that “the First Amendment protects your right to be here and mine” was ignored. A social media avalanche has now piled on a media studies professor who called for “muscle” to push another photographer out of the way.

Some student rights advocates seem convinced that their needs and safety can be assured only by restricting speech. They demand “trigger warnings” on syllabuses, safe spaces on campus where unwelcome views are excluded and de facto prohibitions on potentially offensive forms of expression — including poor-taste Halloween costumes.

The restrictions they seek would not be imposed by the government, or even necessarily the university administration, but by the students themselves and the anonymous armadas of online ostracizers who might rally to their cause. As all sides in this conflict are fast learning, the penalties of online pariahdom — damaged careers, vows of physical harm — can chill speech just as cold as the threat of jail.

On the flip side, among defenders of free speech, conservative and liberal alike, the students’ outbursts are met with dumbfounded incomprehension, laced with ridicule. Students are brushed off as a misguided generation of hothouse flowers. Their fears for their own physical and emotional “safety” are dismissed as Salem-style hysteria.

Both sides are wrong. The dispute is too often framed as a binary match between an emphasis on individual rights — to speech, opinions and Halloween costumes — and the communitarian drive to create campuses bound by shared values and girded against outside intrusion. But these are hardly mutually exclusive. On the contrary, the United States does a better job fostering coexistence between individual liberty and respect for minorities than nearly any other society.

Student protesters needn’t give up their drive to nurture and protect diverse communities in order to accommodate free speech. In fact, free speech is an essential dimension of vibrant campus communities. Who would trade their free-range spirit for the dreary sameness of a corporate office, with its federally sanctioned posters on what constitutes unlawful discrimination?

Free speech has long been a potent weapon for disenfranchised groups, used to expose repression and prevent the powerful from silencing dissent. As John Lewis, the civil rights activist and Democratic congressman from Georgia, said, “Without the media the civil rights movement would have been like a bird without wings.” For champions of the marginalized to curb opposing speech denies them the moral standing to resist the university’s efforts to silence them. The Missouri protesters have hearteningly awakened to this point, standing up for the photographer whom they had shunned.

Moreover, without free speech, the “safe spaces” students crave will soon suffocate them. Social movements must evolve or they die. Ideological and even tactical evolution demands willingness to hear out heterodoxy.

Likewise, free speech defenders will not win by dismissing students as insolent whiners. These students are smart and enterprising. While some ringleaders may fall within the distinguished American tradition of overzealousness in campus protest, the Missouri football team can’t be written off as a bunch of cosseted wusses.

Administrators and commentators need to acknowledge students’ well-founded concerns. They are bent on eradicating the vestiges of overt racism, as well as the prejudices and inequities that fuel it, and are demanding that the leadership of their institutions join the push.

Instead of deriding trigger warnings, safe spaces and censored Halloween costumes, free speech proponents need to advance alternatives that resonate with the students they want to reach. Instead of insisting that individual rights not be subordinated to the ethic of the community, advocates need to explain how free speech can fortify that ethic. They need to tackle ways that racism and discrimination can themselves chill speech.

But they also need to be vigilant when the marketplace of ideas fails: when speech crosses into threats or harassment, or is used to shut down opposing speech. Authorities must intervene not on the side of one or another opposing speaker, but to right the marketplace on behalf of free speech itself — by convening dialogue, providing security for speakers and acting to address the underlying concerns that fuel calls to suppress speech.

The Black Lives Matter movement and the campus protests are efforts to jump-start a drive for racial equality that has stalled in key areas. Free speech is essential to that quest.

Suzanne Nossel is the executive director of PEN American Center.