Last weekend, Lia Thomas — a male athlete who identifies as female — claimed the 100-yard, 200-yard, and 500-yard freestyle titles in the Ivy League Women’s Swimming Championship. A video clip showing Thomas dominating the 500-yard competition sparked outrage, as commentators rushed to defend Catherine Buroker (who finished second) as the true winner.

Thomas, it would seem, has a different perspective. Last month, a female teammate speaking to the Washington Examiner explained that Thomas says “she is like the Jackie Robinson of trans sports.” Conflating the transgender policy agenda with the 20th-century fight for civil rights may be a common activist tactic, but it is also absurd.

The youngest of five children, Jackie Robinson was raised in California by a struggling single mom, and excelled in every sport he ever tried. He wound up playing baseball for the Kansas City Monarchs of the Negro Leagues, then, in 1947, gained national attention when Branch Rickey recruited him to the Brooklyn Dodgers where he broke the major league’s color barrier. “Rickey knew [Robinson] had the strength of character, not just the talent, to over-come the taunts that would come,” Louis Effrat of the New York Times explained at the time.

Robinson was no stranger to racist abuse. He had served in the Army and was nearly court-martialed after refusing to obey a Texas bus driver’s demand to sit at the back with the rest of the black passengers. Yet his talent and tenacity endured. By the time he retired, Robinson had recorded a .313 batting average, 972 runs scored, 1,563 hits, and 200 stolen bases. As for his legacy, he stood in bold defiance of racial segregation and inspired a generation of young black athletes to do the same. Martin Luther King Jr. singled Robinson out for his commitment to civil rights. “Without him, I would never have been able to do what I did,” King said.

Jackie Robinson had incredible talent and a worthy cause. Lia Thomas has neither.

The argument for white-only sports leagues was founded on the general racist assumption that whites were (politically and morally) superior to blacks. That was obviously wrong. By contrast, the justification for women-only sports leagues is rooted in the specific scientific understanding that (physically, and in the context of competitive sports) women are inferior to men. That is obviously correct. There was no reason to think that Jackie Robinson, by being black, had an unfair advantage over the other players. The abuse he suffered was based solely on the color of his skin. There is, however, every reason to think that Lia Thomas, by being male, has an unfair advantage over female competitors. Moreover, only those supportive of Thomas are interested in talking about transgender identity. To everyone else, the issue at hand is sex-based advantages.

That men are on the whole faster and stronger and have greater endurance accounts for the performance gap in elite sports. It also helps explain why women are uniquely at risk from male violence. And it is the reason we have long strived to ensure that privacy, safety, and fairness for women are upheld in law. This is why Congress enacted Title IX in 1972 (as discussed in the Independent Women’s Law Center and Independent Women’s Forum’s new report). Conflating racial segregation with single-sex sports confuses the powerful with the underdogs and the oppressors with the oppressed. It also leads to the insulting conclusion that female athletes protesting male domination in sports are no better than racists.

Though transgender ideologues claim otherwise, Thomas cannot opt out of the male sex category. Sex is an immutable characteristic; Thomas, having completed puberty, has been bestowed with irreversible physical advantages. Jackie Robinson excelled in the “Negro League” as he did in the Major Baseball League, whereas Thomas was a mediocre athlete when he competed in the men’s league. He didn’t improve after transitioning genders; the competition — being female — got weaker.

Robinson wanted black athletes to be taken just as seriously as whites at the national level. He fought for that right with quiet determination. He did so on behalf of other black athletes. Today, it is female athletes who are fighting for the right to be taken seriously. They are the ones whose rights are being trampled on, who face humiliation and bullying. That’s why the real Jackie Robinsons are the young female athletes such as Selina Soule who have taken a stand against this sexist injustice.

Thomas told UPenn’s student paper last year that “being trans has not affected” his “ability to do this sport and being able to continue is very rewarding.” But of course it hasn’t. Again, the issue isn’t “being trans.” The issue is being male in the female category. Hijacking the legacy of the civil-rights movement to deprive female athletes of equal opportunity is inexcusable. The only thing Lia Thomas and Jackie Robinson have in common is their sex.