How many of us have received a phone call from our mothers these past few weeks, demanding to know why young women aren't lining up behind Hillary Clinton? It's the question that launched a thousand think pieces, some of them going so far as to declare second-wave feminism dead among millennial women. And indeed, Bernie Sanders drew an impressive percentage of the female vote in New Hampshire's presidential primary last week, performing especially well among women under 30.

It's puzzling and exasperating for many feminists that with the first real chance of a female US president on the table, college-age women just don't seem that into it. Feminist icons Gloria Steinem and Madeleine Albright both recently vented these frustrations, making statements they later walked back.

But from our vantage point as women in our 30s, it's not so surprising that very young women don't feel the same excitement about a competitive, hyperqualified female candidate for the presidency that their mothers, aunts, and older sisters do. For them, the world may seem like a much more equal place than it actually is.

After all, we've come a long way since the early days of the women's rights movement. In school, girls now outperform boys by many measures. Women enroll in and finish college at higher rates than men. And these days, no one tells you to give up on your dreams of medical school, find a husband, and settle down. Pioneers like Ruth Bader Ginsburg and Sandra Day O'Connor were the only women in their law school classes and were refused clerkships and jobs on the basis of their sex. Today, approximately equal numbers of men and women graduate from law school, and four in 10 graduating MBAs are women.

For younger women, the world may seem like a much more equal place than it actually is

Looking around in college or grad school, it's easy to believe that, in the United States at least, gender equality has largely been achieved. It was for us: We both self-identified as feminists from an early age, but it was a feminism mostly concerned with solidarity —with survivors of wartime sexual violence, with women campaigning against female genital mutilation in their communities, with girls forced to work inside the home instead of going to school. It didn't feel like our rights or well-being on the line.

But it turned out they were — we just didn't know it yet. The progress made by previous generations of feminists means that women have by and large achieved equality in education and early career prospects. And the social change that accompanied this progress has seen more and more women delay starting families in order to take advantages of these opportunities. But there's a reason that recent interventions focused on barriers to women's ascent into the leadership ranks in politics and business and struggles with the work-life balance have been so widely read and talked about.

Because once women enter the professional world, the rosy picture of progress begins to dull. Only 15 percent of law firms' equity partners are female. Women make up only 3 percent of hedge fund managers and 1.5 percent of CEOs of large corporations. And women only account for 37.5 percent of tenured faculty in American universities. This absence of women leaders and experts is so notable that it's become something of an in-joke, with a dedicated Tumblr declaring, "Congrats, you have an all-male panel!" and a crowdsourced database of women political scientists called Women Also Know Stuff, aimed at journalists who only quote men. Women who do ascend the ranks of predominantly male professions face other obstacles — misattribution of their successes to male colleagues, widespread sexual harassment, the threat of violence, and more.

And at the same time that women are getting serious about their careers, many are also thinking about starting families. Women get married and have children later than they ever have before. In 1959, Madeleine Albright got married at the august age of 22 — two years older than the average bride at the time. By 2015, the average American woman remained single and childless into her late 20s. These statistics vary by ethnicity, educational attainment, and economic status, but they show something important: that professional women in their late 20s and early 30s face a double reckoning. They're confronted with gendered expectations (including their own) about family on the one hand and sexist barriers to their career advancement on the other.

These dynamics can be a rude awakening for young women who have excelled all their lives, often at institutions that have invested resources, time, and attention into recruiting promising women. They're experiencing something we call "late-breaking sexism." It's the sudden realization that you don't have the same opportunities as a man, that you will struggle to have both a family and a career, that your participation in the public sphere will always be caveated by your gender.

In short, that although latter-day feminist icons encourage women to "lean in," they will be met at every step of the way by someone telling them, implicitly or explicitly, to "get back."

Women in their late 20s and early 30s face a double reckoning — they're confronted with gendered expectations about family on the one hand, and sexist barriers to their career advancement on the other

It wasn't until we hit that moment of embarking simultaneously on professional lives and family lives that feminism felt personally meaningful and urgent. But it's felt that way every minute of every day since then — when we learned that our teaching in graduate school would be held to a different standard than that of our male colleagues; when we're assumed by male officials to be present at high-level meetings to fetch coffee, not share our expertise; when our friends struggle to pump breast milk in dingy closets at law firms that have just spent tens of thousands of dollars upgrading their office floral arrangements.

Our experiences in many ways reflect an incredibly privileged position, and it would be silly to suppose that they are representative of all women. But we do think it's relevant for understanding the particular group of young, educated, politically engaged women whose lack of enthusiasm at the prospect of a female president is causing so much consternation.

Women can go a lot further in life than they used to before they experience sexism and gender inequality as structural forces that shape their lives. Sure, by age 18 most of us have been the targets of gender stereotyping and sexual harassment. By the time we graduate from college, one in five of us will be a survivor of sexual assault. But we can write off these experiences as the actions of individual perpetrators. And many young women are inclined (as we were) to look at it that way rather than think of their biological sex as something that's holding them back.

That's not to say that these young women aren't good feminists. They are. Young feminists are doing the hard and necessary work of forging a more inclusive movement, one that's here for women who aren't white, straight, cisgender, able-bodied, or upper middle class. But it explains why the more "orthodox" feminism of Hillary Clinton, Gloria Steinem, and Madeleine Albright, with its focus on the workplace, doesn't necessarily resonate for them.

Young women don't owe Clinton their votes. Democrats are lucky this year to have a choice of two thoughtful candidates, both of whom are infinitely superior on women's issues to the candidates crowding the Republican field. But if millennial women aren't inspired by the Sisterhood of the Traveling Pantsuit's call to arms, or starry-eyed at the prospect of a female commander in chief, we wonder if they might feel differently in a few years.

Thanks in large part to the activism and advocacy of women who have been fighting for equality for decades, the structural barriers to success that young women face have been reduced in their height and delayed in their onset. But they're not gone. And for many women, those barriers will emerge suddenly and without warning in their late 20s and early 30s, when critical career and family life junctures occur. That's when it becomes hard to escape the fact that women still face systemic disadvantages in their pursuit of careers, and misogynistic backlash to their participation in public life. Late-breaking sexism often means later-onset identification with the principles of second-wave feminism. Reports of its demise, however, are greatly exaggerated.

Dr. Kate Cronin-Furman is a postdoctoral fellow at the Center for International Security and Cooperation at Stanford University; Dr. Mira Rapp-Hooper is a senior fellow in Asia-Pacific Security at the Center for a New American Security in Washington, DC.

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