Michael B. Jordan has been cast as Johnny Storm in the new Fantastic Four movie. For many prospective viewers, that announcement will raise the question that any announcement of a Michael B. Jordan movie raises: Will he be shirtless, and for how much screen time? Other superhero fans, though, are distracted by less wholesome concerns. Johnny Storm, they have noticed, is White. Michael B. Jordan is Black. How, they wonder, can this be?

The outcry over interracial casting here appears to be much more muted than the stir over Idris Elba's role as Heimdall in the Thor franchise, which provoked boycott threats. Still, I've seen people on Twitter talking about how the casting will "ruin" the franchise. I'm not going to link because I'm leery of shaming people that way on a mainstream site, but if you look around you can find them without too much trouble. This echoes earlier controversies in which a campaign to get Donald Glover cast as Spider-Man met with racially fraught backlash, while the casting of Amandla Stenberg as Rue in The Hunger Games provoked angry social media whining.

People say they object to Black casting because it's untrue to the original source material, and a betrayal of the characters—a claim that seems particularly dicey in the case of The Hunger Games, where Rue is Black in the original novel. But even in the case of the Fantastic Four, where Jack Kirby and Stan Lee did in fact make the team White, the plea to be faithful to the founding seems to raise a lot of questions.

After all, it's not like there's been one, true, unwavering Fantastic Four over the decades. The Thing was originally drawn by Jack Kirby as a lumpy mess; it took a while for him to settle down into the more-streamlined orange form fans know and love. Sue Storm at first could only turn invisible; it was some time before she developed the invisible force fields that made her useful in a fight. For that matter, She-Hulk replaced the Thing on the team for a while. And then there was a popular series where the Fantastic Four turned into zombies. Comics are serial soap-opera fantasies; people change costumes, grow blue fur, die, grow a third eye, come back to life, are replaced by a clone and turn to the dark side. Nothing stays the same. Why, then, is this particular, relatively minor alteration in canon seen as a betrayal?

You could argue that racial difference is more noticeable, or different in kind, than plot-driven death or blue fur or zombiefication. But then, how account for the fact that in the comics characters like Iron Man, Spider-Man, and Green Lantern have, at various times, been Black? More, certain changes in racial background or casting seem to provoke little comment. No one, as far as I'm aware, has complained about Scarlett Johansson's casting as the Black Widow on ethnic grounds. Yet Johansson’s background is Jewish. The original Black Widow, Natalia Romanova, has what appears to be an ethnic Russian name; there was no indication that she was originally supposed to be Jewish. Given the anti-Semitism in Cold War Russia, a Jewish ethnic identity would in context be a significant alteration to the character. Why, then, do people care about Storm, but nobody cared about Romanov? 

The answer is obvious enough. American racism holds that only certain racial differences matter.