FOR an hour or two on a foggy morning last December, some students at the University of Iowa (UI) mistook one of their professors, Serhat Tanyolacar, for a fan of the Ku Klux Klan. Mr Tanyolacar had placed a canvas effigy based on Klan robes, screen-printed with news cuttings about racial violence, on the Pentacrest, the university’s historic heart. The effigy had a camera in its hood to record public reactions.

The reaction among some black students was to fear for their safety, and that is not surprising. What is more of a puzzle—for anyone outside American academia, at least—is that students and UI bosses continued denouncing Mr Tanyolacar for threatening campus safety even after the misunderstanding was cleared up. In vain did the Turkish-born academic explain that he is a “social-political artist”, using Klan imagery to provoke debate about racism. Under pressure from angry students, university chiefs issued two separate apologies. The first expressed regret that students had been exposed to a “deeply offensive” artwork, adding that there is no room for “divisive” speech at UI. The second apologised for taking too long to remove a display which had “terrorised” black students and locals, thereby failing to ensure that all students, faculty, staff and visitors felt “respected and safe”. An unhappy Mr Tanyolacar feels abandoned by the university. He left Iowa earlier this month, when his visiting fellowship came to an end, and has suspended his teaching career.

A crucial word in this tale is “safe”. Campus activists have stretched the meaning of safety from an important but second-order concern—shielding students from serious harm—to a defining ambition for any well-run academy. From town-sized public universities to tiny liberal-arts colleges, students have declared and administrators accepted that teachers or visiting speakers should aim for a psychologically safe learning environment, avoiding ideas or imagery that might prove distressing.

Activists sometimes organise campus “safe spaces” where students may flee alarming material. Door-stickers denote full-time safe zones for specific groups, such as gay and transgender students, or religious non-believers. Demands have multiplied for “trigger warnings”—a device first seen in self-help and feminist internet forums, signalling content that may trigger painful memories—to be applied to challenging books, films or lectures.

Not every demand succeeds. In 2014 a backlash obliged Oberlin College in Ohio to withdraw sweeping guidelines urging teachers to think before setting triggering coursework. Oberlin’s guidelines included a specimen warning for “Things Fall Apart”, a pioneering Nigerian novel, noting that it might “trigger readers who have experienced racism, colonialism, religious persecution, violence, suicide and more.” Students at Wellesley College, which is women-only, failed to have a statue moved indoors, despite a petition blaming it for campus-wide fear: it was a life-like depiction of a sleepwalking man clad only in saggy underpants.

Not all trauma is imagined. Many colleges spent years downplaying sexual assaults on students. But even sympathetic teachers worry that tools intended to fight real ills are being misused, including Title IX, a civil-rights statute that, among other things, obliges universities to ensure that women do not face a “hostile environment”. Laura Kipnis, a feminist scholar at Northwestern University, caused a stir when she revealed that students had sued her under Title IX after she wrote that some sexual-harassment complaints are exaggerated. Ms Kipnis was cleared after a 72-day investigation.

Such rows prompt conservative glee and leftish gloom. Pundits see a reap-what-you-sow irony, as politically correct culture warriors of the 1980s and 1990s are devoured by their own heirs. There is much mockery of youngsters as sensitive “snowflakes”. An online essay headlined “I’m a liberal professor, and my liberal students terrify me” went viral.

Not what, but who

Yet Mr Tanyolacar’s troubles point to something new and alarming. A generation ago campus rows turned on what should be taught. Leftish students decried lessons about dead white men as acts of racist and sexist oppression. UI witnessed its own censorship battle, after a conservative student complained about gay sex scenes in a German film shown in class. But what Mr Tanyolacar was saying was not the problem: his work is explicitly anti-racist. His problem turned on who now has the authority to declare his art harmful, regardless of his intent.

The alarm about the Pentacrest effigy was sounded on social media by Yasmin ElGaali, a second-year undergraduate. She noted that the students had gathered on the same spot, the night before, to protest against police killings of black Americans. Kayla Wheeler, a doctoral student who had organised that protest, hurried to the scene, fearing a personal threat. Both women recall arguing with the artist. Ms ElGaali says that he was “very condescending” when black students told him that his work was hurtful and triggering. Mr Tanyolacar says that he was provoking a conversation about race. Ms Wheeler challenges his right to do that, saying: “I don’t understand why a non-black person can appropriate black people’s pain to teach a lesson about racism.” Tom Rocklin, UI’s vice-president for student life, says the effigy was erected without permission and should have been labelled, not sprung on students. He calls the incident a transformative moment for race awareness, on a campus that is 3% black.

Some colleges have less noble reasons for bowing to students, starting with financial pressure to keep enrolments up. Unfortunately for them, something called the American constitution strongly protects free speech, whether divisive, upsetting or not.

At root this is a fight about power, with feelings wielded as weapons. Students should beware of winning too many victories. A perfectly safe university would not be worth attending.