Mike Segar / Reuters

PHILADELPHIA—“Daddy,” my daughter recently asked me, “Why are there no girl presidents? Is it because boys are stronger than girls? Because they’re smarter?”

It left me speechless.

On Thursday night, in the city where the Founders declared all men created equal, I found my answer. It’s because no major party has ever tried nominating one before.

“Tonight, we’ve reached a milestone in our nation’s march toward a more perfect union: the first time that a major party has nominated a woman for president,” Clinton said as she accepted the nomination. “Standing here as my mother’s daughter, and my daughter’s mother, I’m so happy this day has come.”

It wasn’t the theme of her speech. But it was the unspoken subtext that ran through it. And Clinton took pains to frame the achievement not as the triumph of some subset of Americans, but as a victory for all Americans. She proclaimed herself both “happy for grandmothers and little girls,” but also “happy for boys and men—because when any barrier falls in America, it clears the way for everyone.”

It’s a barrier that proved surprisingly enduring.

Women constitute 51 percent of the American population, cast 53 percent of the votes in the last presidential election, and earn 57 percent of the bachelor’s degrees. It’s easy to look at those numbers, and believe the election of a woman to the highest office in the land an inevitability. And for a long time, people have.

In 1888, the prominent suffragist Isabella Beecher Hooker confidently predicted that, “we shall have a women president of the United States before the ballot is given to women.” In 1905, Supreme Court Justice David Brewer told an audience that “before gray hair shall cover the heads of the women here tonight” America would send a woman to the White House.

But the 19th Amendment was ratified in 1920; Brewer’s listeners greyed, and then passed. A century later, the election of a woman remains perennially inevitable, perhaps even imminent, and yet somehow unachieved.

Women now occupy a broad range of business, professional, and civic positions. But in politics, as in most other fields, it gets narrower toward the top. Not quite one in three local and county officials is a woman, but only one in four state legislators, one in five members of Congress, one in eight governors. And no presidents.

That may not change. There’s no shortage of reasons for voters to dislike this particular woman—indeed, most do—and presidential elections present binary choices. But even voters marking their ballots for Trump will look at them and see something new. And maybe the chance to vote against a major-party nominee who happens to be a woman is itself a mark of progress, just as much as the chance to vote for her.

Even if Hillary Clinton wins, it wouldn’t bring about a post-gendered American, anymore than Barack Obama’s victory delivered a post-racial America. Indeed, there’s every reason to expect it to produce a wave of open misogyny, as ugly as the racist backlash of the Obama years. It’s Newton’s Third Law of Cultural Politics: Every action creates an entirely disproportionate and opposite reaction.

But for now, at least, misogyny is just one of the varied hatreds and hostilities coursing through American politics. The race between Donald Trump and Hillary Clinton hinges on many things, and matters for many reasons—and neither her staunchest supporters nor her fiercest opponents tend to put gender at the top of those lists. But both the daughters of the delegates in Cleveland who chanted, “Lock her up!” and the sons of the delegates in Philadelphia who shouted, “I’m with her!” will grow up knowing that a woman can win a nomination, and perhaps the presidency. In fact, they’re unlikely to ponder the possibility that it could be otherwise.

That’s how it works when barriers fall; it’s hard to remember they were ever there at all.    

“We hold these truths to be self-evident,” reads the Declaration signed in Philadelphia, “that all men are created equal.” In her speech, Clinton quoted lyrics from the musical Hamilton. But there was another couplet, from a different song, that she didn’t even need to repeat aloud: “We hold these truths to be self-evident, that all men are created equal,” the heroine, Angelica Schuyler, sings. “And when I meet Thomas Jefferson, I’mma compel him to include woman in the sequel.”

Hillary didn’t take the stage until well after 10 p.m., but all evening, parents filtered in to the Wells Fargo Arena with children in tow. A disproportionate number seemed to be girls. By an escalator, I found Patricia Ewing, who had brought her two daughters from Annapolis, Maryland, to share in the historic moment. “It’s a huge sea change in the possibilities for them,” Ewing said.

Her 14-year-old, Veronica, was less enthused. “Originally I was for Bernie,” she explained, “but since he wasn’t going to make it, she was the second best compared to Trump.” As we talked about the historic import of the moment, her 13-year-old sister turned her back to watch the crowd. I asked her what she thought. “I really don’t like Trump,” Sofia said. “I’d much rather have Bernie, but as long as it’s not Trump.”

Others were more enthusiastic. Eighteen-year-old Zach Rosenfeld had come along with his father, Tom, and his 14-year-old brother. “I’m a huge Hillary fan,” he said, “and we’re about to see history made.” His high school sits a block away from Clinton’s campaign headquarters in Brooklyn. “To watch your kid so excited about the democratic process … is a real gift,” his father said.

They were watching when Hillary Clinton looked up at them and said: “Even more important than the history we make tonight, is the history we will write together in the years ahead.”

“I remember looking up at the poster on the wall of our American presidents,” Ohio Senator Sherrod Brown recalled of his third-grade classroom. “Other than a few mustaches and powdered wigs, they all looked pretty much like me.” His grandchildren, he said, “won’t see faces that look only like mine, they will see Barack Obama, and because of the work that we do over the next 100 days, my granddaughters will see themselves in the face of Hillary Clinton.”

Earlier in the evening, Meredith Cabe and her three girls from Silver Spring, Maryland, were grabbing an early dinner on the concourse. “The reason we came is these guys,” Cabe said. “It’s an amazing thing that it’s part of their childhood.”

“I want to see Hillary and to see her speak and to see her get nominated,” said Lila Hutchins, her 10-year-old. It was important, she said, “because if she’s the first woman president then there’ll probably be other ones.”

Her 6-year-old sister, Mae, broke in excitedly: “I know I will be one!”

She beamed up at me, and I believed her.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.