Major League Baseball is increasingly closer to having its first female professional ballplayer, thanks to Melissa Mayeux. The 16-year-old French shortstop joined MLB’s international registration list on Sunday, making her eligible to play professional baseball in the United States.

As with every other prospect on that international registry, it’s a long shot that Mayeux will make the big leagues—and experts think it would be years before she is, if ever, signed by a team.

Still, Mayeux is now the woman most likely to step into the batter’s box in a Major League stadium. No doubt, the addition of her name to the registration list is the exciting for fans who would love to see a woman break the glass ceiling on professional baseball.

But all the attention is also stark reminder that when and if a woman finally gets to partake in our national pastime on a professional level, she most likely won’t be homegrown.

Baseball is cherished as part of our national identity, hallowed in an endless array of books, movies, and poems, from The Natural, to The Boys of Summer, “Casey at the Bat,” Eight Men Out, and Field of Dreams. Even though it’s not the most profitable or the most popular sport in the U.S., baseball seems integral to the American identity in a way no other sport is.

Yet we actively keep women from participating in baseball, instead encouraging young girls who like the sport to pursue softball instead. The division of men in baseball and women in softball is so entrenched in U.S. sports that we rarely take a moment to ponder that the split is neither natural nor necessary.

Japan offers women the opportunity to play baseball on a college level. Indeed, the Japanese have already reached out to Mayeux about playing at that level, Boris Rothermundt of the French Baseball Federation told The Daily Beast. Canada and Australia also have notable women’s baseball programs. France and other European nations actually “changed the rules in December because of Melissa and her level of play” to allow her and other women to play in higher leagues, Rothermundt said. However, even before the rule change, France and other European countries had established under-15 baseball teams for girls and teens.

“We are Neanderthals in claiming this is a national pastime and keeping it closed to half the nation,” Jennifer Ring, author of Stolen Bases: Why American Girls Don’t Play Baseball told The Daily Beast.

“It’s separate but equal,” Ring said dismissively of the practice of pushing U.S. girls into softball and boys into baseball. “We know how well that worked out for civil rights.”

Ring has spent several years researching women in baseball and interviewing the relatively few U.S. women who have played at the NCAA level. She estimates there have been “fewer than a dozen in history.”

“There are a lot of institutional impediments in the U.S. that don’t exist in other countries,” Ring said. She cites how NCAA baseball only has men’s teams, so if a young woman wants a chance at an athletic scholarship, she is incentivized to play softball, even if baseball is her true passion.

Because at the NCAA and, for that matter, the high school level, there are no separate baseball team options for women—unlike for soccer, hockey, basketball, and a host of other sports—women who want to pursue the national pastime must physically hold their own against men if they want to play at all.

“A girl playing on a boys’ high school team has to be as fast as a boy, as strong as a boy, and hit as hard as a boy,” Ring points out. Even if a girl ditches baseball for softball, her professional options generally dry up after college.

“We think of a man when he’s 20 at the start of his professional career. With girls, you’re over, you’re done,” said Ring. Some of the women she interviewed likened that personal realization to “being pushed off a cliff,” she said.

Ring argues that a long and concerted effort to keep women out of baseball goes back to the mythology surrounding the sport’s origin.

While it is widely believed that Abner Doubleday invented baseball in mid-19th-century America, that myth has been debunked. The sport likely had its origins in England, said Ring, and actually with women. Stoolball, a game played by Sussex milkmaids centuries before baseball hit the U.S., is considered one of forebears of the sport.

Even during the 19th century, women played baseball at the Seven Sisters colleges, said Ring. “Early baseball was not a man’s game. It was turned into a man’s game for ideological reasons,” she said.

Baseball grew increasingly popular in the U.S. at the turn of the 20th century, in the same period when the U.S. was rising on the world stage. It was a time when Theodore Roosevelt was glorified for leading the Rough Riders in the Spanish-American War. His 1899 speech “The Strenuous Life,” encouraged manly strength as a form of patriotism—an attitude embraced by many at the time.

“Baseball was getting associated with the national identity when the U.S. was just emerging out on the global scene as a power. You needed it to be manly. You couldn’t have your national game tied to your national identity be effeminate,” said Ring.

It was around this time, she said, that women started to be encouraged to play softball, even though men had previously been playing the sport. “There’s this strident ideology that baseball is for men, and softball is presented as a less competitive, less strenuous, less challenging version,” she said.

Still, women were clearly were playing baseball. As anyone who has seen 1992’s A League of Their Own knows, women even played baseball on a professional level in the U.S. The All-American Girls Professional Baseball League began in 1943 to fill the baseball void as Major League players went off to war. Female ballplayers were getting dirt in the skirt until 1954.

However, like so many advancements for U.S. women during World War II, baseball later ceased to be a professional option. “In the 1950s, we shoved women out of everything,” Ring said. “We have this unfortunate decade for women in American history. It’s a decade when women are sent back into the home.”

With the women’s liberation movement and Title IX, sports reemerged in the 1970s for women, but baseball did not. “Baseball never turned a corner and opened the doors to women,” said Ring.

Indeed, there’s evidence there was a concerted effort to keep girls out of baseball. In 1972, the national Little League organization threatened to revoke the charter of a team in Hoboken, New Jersey, because they allowed 12-year-old Maria Pepe to play. The National Organization for Women took on the case and successfully sued to allow for Pepe and other girls to be able to try out. In response to the pressure, Little League created Little League Softball.

Since then, there have been American girls and women who have gained national attention for their baseball skills. That’s usually because against all odds, they have survived on teams established almost exclusively for boys or men.

Case in point: Mo’ne Davis, who vaulted into the national spotlight when she became the first female pitcher to win a game in the Little League World Series. Just this week, Davis signed with the Harlem Globetrotters and has publicly discussed her desire to pursue basketball instead of baseball.

Davis’s decision makes perfect sense to Ring. “There are more venues for her. Basketball is something a girl can expect success at,” she said.

When I pointed out to Ring that the WNBA is not nearly as profitable or popular as the NBA and thus doesn’t provide the same opportunities for female and male players, she doesn't disagree. However, she doesn’t see that disparity as insurmountable or natural but rather as a reflection of an ingrained bias toward female athletes

“I think we don’t want to market women’s sports, especially team athletes. We don’t have the same problems with tennis, golf, or swimming, but to take a women’s team sport and make it central to American culture is going to require some changes. There’s a psychological obstacle to embracing athletics as a career path for women,” she said.

But Ring is hopeful—in a cynical sort of way:

“We can do it. We can market anything. The U.S. has never come up short in ingeniousness about marketing.”