Every year in the small California town where I grew up, the men who ran the Lompoc Little League would put on a “Powderpuff” game where the mothers of the boys would take the field. The idea was for everyone to have a chuckle watching the women “play like girls” as they floundered around on the field.

My mother, who was a star in the All American Girls Professional Baseball League in the 1940s, would put on a display of hitting, throwing and fielding that left the men in the stands staring dumbfounded, realizing that she was better at the game than they could ever hope to be.

When I entered high school in the 1970s, a political development took place that changed the nature of women’s athletics that resonates to this day. The federal government intervened to force our schools and universities to provide equal opportunity for female athletes in a way that would have been unfathomable for my mother’s generation.

Congress passed a civil rights law called Title IX of the Education Amendments of 1972, which prohibited discrimination against girls and women in federally funded educational institutions. The law applied to both public and private institutions that receive federal funds, and stipulated that women and men be provided equal opportunities to all educational resources—including athletics.

Indiana Senator Birch Bayh and Hawaii Representative Patsy Mink sponsored the law. Bayh, speaking on the Senate floor, stated that the era of stereotyping women as “pretty things,” who were unable to compete at the highest levels of education, business and athletics was over. Mink played basketball in high school for Maui High but was limited to half-court games due to the stereotypes Bayh spoke of.

Since 1972, women’s participation in sports has skyrocketed. According to a recent survey by the National Federation of High School Associations, fewer than 300,000 females participated in high school sports before 1972. From 2017 to 2018, according to the association, 3.4 million girls engaged in high school athletics.

The path of Title IX since 1972 has not been smooth. Politicians and colleges have fought against what they argued were overly restrictive interpretations of “proportionality”—the proviso that if half of a university’s students are female then half of the student-athletes must be female. And attempts were made to exclude revenue-producing sports—mostly male—from Title IX’s purview.

When the Supreme Court narrowed the scope of Title IX in the 1984 decision Grove City College v. Bell, women’s sports programs were left without legal protection because so few received direct federal funding. It took the Civil Rights Restoration Act of 1988—passed over President Ronald Reagan’s veto—to clarify that if any part of a college or institution accepts federal financial assistance, Title IX covers the whole college.

While Title IX does not require that equal amounts of money be spent on men and women’s sports programs, it does mandate equal treatment be provided with respect to equipment, practice, travel, tutoring, medical and training facilities and recruitment.

The recent triumph of the U.S Women’s National Soccer Team—celebrated today with a parade in New York—is a direct result of Title IX. The team has now won four World Cups, more than any other country. In countries where men’s teams are major powers–-like Argentina, Spain and Brazil—their women’s teams have floundered without the advantage of our earlier commitment to parity.

Julie Foudy, co-captain of the 1999 World Cup Champion team, told 60 Minutes that “We [the team] were Title IX babies.” With the success of early women’s teams, tens of thousands of young girls began wearing jerseys with the names of their heroes Mia Hamm, Brandi Chastain and Abby Wambach stitched on the back.

Megan Rapinoe scored six goals in World Cup play this year. She caused a minor kerfuffle when she said she would not visit the White House if the team won the World Cup because she did not want to be “co-opted” by a president who does not share her, or the team’s, values.

Many Americans believe that sports and politics should not mix. “Shut up and dribble,” as Fox News host Laura Ingraham famously said about LeBron James after he mildly criticized President Trump. Coddled and overpaid professional athletes need to shush.

But with women’s soccer, not only are they not overpaid, they are not even close to parity with the men’s team. On March 8 of this year—International Women’s Day—all 28 members of the women’s national team filed a gender discrimination lawsuit against the US Soccer Federation for “intentional gender discrimination.” The absence of pay equity is a major element in the suit.

Writing in The New York Times, journalist Jeré Longman called Rapinoe a “representative athlete of our times.” Indeed, she is. Like Jackie Robinson, Muhammad Ali, Billie Jean King—and my mom—Rapinoe’s outspokenness and political commitment befits a generation of women who will not stop until they have achieved justice.

The push for women’s equality on the athletic fields was not a simple “top down” process. A burgeoning women’s movement in the 1960s and grass roots dynamics—including the founding of the American Youth Soccer Organization in 1964—helped create the political will that pushed politicians towards bolder proposals.

On Sunday the national team held the World Cup above their heads and pointed out that politics and sports are inextricably linked. Several players unabashedly backed up Rapinoe’s outspokenness—including veteran defender Ali Krieger who pointed out that playing and speaking about politics was simple “multitask[ing].” Remaining silent, Krieger added, would be siding with an “oppressor.”

Beyond opposition to Trump and his defenders, Rapinoe, Krieger and the others understand that while some athletes may be born with great talent, successful national teams need a supportive society. They stand on the shoulders of fine female athletes who came before them, and political leaders who fought for them at the highest levels of our government.