This being the United States in 2017, Internet trolls are accusing “Star Trek: Discovery,” the newest incarnation of the sci-fi franchise, due to début on television in the fall, of white genocide. The commotion began last week, when the show’s trailer first appeared on YouTube. It opens with a conversation between the two lead characters, a starship captain and her first officer, played by Michelle Yeoh and Sonequa Martin-Green, both women of color. Very quickly, the comments section was filled with garden-variety Trekkie gripes—the Klingons looked weird, there was too much lens flare, the dialogue was hammy, the uniforms were non-canonical. Many commenters, though, were clearly appalled by the absence of white men in command positions. “Where is the alpha male that has balls and doesn’t take crap from anyone?” one asked. “Is everything going to have to have females in every fucking thing?” another asked. A third person called Yeoh “a reject from a overseas customer-support line.” A fourth dubbed the show “Star Trek: Feminist Lesbian Edition.”

Two and a half years ago, in the very same corners of the Internet, there was a similar campaign against “Star Wars: The Force Awakens,” whose trailer featured a female protagonist and a black man wearing the iconic white carapace of a Storm Trooper. That incident was absurd enough, but in the case of “Star Trek” the outrage is even more confounding than usual. The franchise’s claim to fame, its central premise, is its advocacy for science, non-belligerence, and, above all, multiculturalism. In its fifty-year history, “Star Trek” has cornered the market on tolerance and cosmopolitanism. Even those who have never watched the original series, which aired in the late nineteen-sixties, likely know that it featured the first interracial kiss on network television—between William Shatner’s Captain Kirk and Nichelle Nichols’s Lieutenant Uhura.

And intergalactic office romance is really the least of it. Each successive “Star Trek” cast has been like a model United Nations. Nichols’s black communications specialist worked alongside George Takei’s Japanese helmsman and Walter Koenig’s (admittedly campy) Russian navigator. Leonard Nimoy’s Spock was half-human, half-Vulcan, and he bore traces of the actor’s own upbringing in a poor Jewish neighborhood in Boston. The Vulcan hand greeting, for instance, which Nimoy invented, is the Hebrew letter shin, the symbol for the Shekhinah, a feminine aspect of the divine. The original series aired only a few years after the Cuban missile crisis, at the height of the Vietnam War and the space race, and its vision of a reconciled humanity was bold. Nichols, who considered leaving the show after the first season, has said that she was persuaded to stay on by Martin Luther King, Jr., who told her that he watched “Star Trek” with his wife and daughters.

Later manifestations of the franchise continued the tradition. The captain of the Enterprise in “The Next Generation” was a Frenchman from Bordeaux (though he spoke impeccable Oxbridge English). The chief engineer, Geordi La Forge, was black, and his colleagues on the bridge included an alien and an android. For seven seasons, “T.N.G.” explored much more than space: it sketched the contours of a modern utopia in which people, freed from material want, could pursue knowledge, justice, and the greater good. The series’ early-nineties spinoff, “Star Trek: Deep Space 9,” went even further. It was a sort of “Casablanca” in space, with characters from all races and worlds and cultures mingling, not always harmoniously, on a lonely outpost. Benjamin Sisko, the station’s commanding officer, was a black man and a single father. His deputy was a female alien and former resistance fighter. And then there was “Voyager,” whose captain, played by Kate Mulgrew, was the only woman to serve as a central character in any of the “Star Trek” series—until Yeoh and Martin-Green.

It is neither surprising nor especially interesting that “Discovery” has caused a conniption among the Bannonite mob. It is, however, a little ironic, because in many ways “Star Trek” falls short of the social-justice-warrior label. In the original series, for example, no one seemed bothered by the fact that short-skirted female crew brought the male senior officers their lunches, or that Captain Kirk seemed barely able to contain his sexual appetites. The series’ bartender, maternal and full of folksy alien wisdom, is played by a black woman, Whoopi Goldberg. Throughout the franchise, there is a complete absence of gay or even mildly gender-fluid characters in Starfleet uniforms. (That erasure was repaired, but only in passing, in the last movie, “Star Trek Beyond.”)

Indeed, “Star Trek” can often be seen as patronizing, if not conveniently delusional. The United Federation of Planets, despite its vaunted tolerance and inclusiveness, is mostly led by older white men. The explorers’ motives are represented as pure, unencumbered by cultural chauvinism, yet their science always prevails over aliens’ indigenous superstitions. By a strange and circuitous logic, the trolls who scream, “White genocide!” have espoused this very argument against the show. In effect, they are pining for the least appealing aspects of “Star Trek,” those that arise from unconscious slips and lingering prejudices, despite the writers’ best intentions. But it seems clear that they are fighting a losing battle. As the franchise continues to evolve to better reflect the tastes and the diversity of a global audience, the trolls will find it increasingly difficult to locate a safe space for their nativist fantasies, on Earth or among the stars.

*An earlier version of this post mischaracterized a "Star Trek" character’s kiss.