In the recent governor’s race in Virginia, Glenn Youngkin scored a huge upset win days after promising to ban critical race theory from Virginia schools. Youngkin is hardly the only Republican calling for school bans. In Texas, Representative Matt Krause sent a letter to school administrators about books in their district. Did they have Ta-Nehisi Coates on their shelves? Isabel Wilkerson’s Caste? How about LGBT Families, by Leanne K. Currie-McGhee? Or any of about 850 other books that might, in Krause’s words, “make students feel discomfort, guilt, anguish, or any other form of psychological distress because of their race or sex”?

Beyond Texas, beyond Virginia, the prospect of banning books and ideas from public schools has GOP strategists smelling electoral blood. House Minority Leader Kevin McCarthy vowed to turn school bans into a winning issue for Republicans in 2022, sketching a “parental bill of rights” to protect kids from troubling ideas about race and sex.

These efforts have a history. Back in the 1920s, the vague term that galvanized conservative angst was not critical race theory but evolution. Conservative pundits at the time seized on a cartoonish misrepresentation of evolutionary science and warned their fellow Americans that “evolution” was nothing less than a sinister plot to rob white American children of their religion, their morals, and their sense of innate superiority.

But although the school bans might have changed some school curricula in the short term, in the long run, they backfired. Telling parents you don’t want their kids to have the best possible public schools is never good politics. A full century ago, the most effective school-ban campaign in American history set the pattern: noise, fury, rancor, and fear, but not much change in what schools actually teach.

In the 1920s, the idea of evolution wasn’t new. Charles Darwin’s bombshell book about natural selection had been published 60 years earlier. The outlines of Darwin’s theory had become standard fare in school textbooks and curricula, even though the real scientific controversies about the mechanism of natural selection were by no means settled. But the furious campaign to ban evolution had nothing to do with those debates among scientists.

In 1923, T. T. Martin, the “Blue Mountain Evangelist,” preached that “evolution is being drilled into our boys and girls … during the most susceptible, dangerous age of their lives.” Evolution, Martin warned, was not good science but only a plot by “sneering” “high-brows” to inject mandatory atheism into public schools. Martin claimed to have “abundant evidence that the teaching of these text-books is unsettling the faith of thousands of students.”