President Trump meets with North Korean leader Kim Jong Un in Hanoi on Feb. 28. (Evan Vucci/AP)
Elena Souris is a research associate in the political reform program at New America.

After months of “fire and fury,” a summit, “beautiful” love letters and a promise the North Korean threat was resolved, the latest nuclear weapons negotiation between the United States and North Korea failed. This isn’t surprising.

We haven’t seen a U.S.-North Korea agreement because nuclear policy is hard. Negotiating takes time, innovation, expertise and having the best minds involved in the process — including women.

But women were notably not represented at the last Trump-Kim summit. At the negotiating table were nine men; the only woman was an American translator. Translating has long been considered a “feminine” job in international delegations. This work powered the United States’ rise over the 20th century, yet it reflects how women have been directed to support male-designed policy rather than contribute to its creation. As our research into women’s history in this field since the 1970s shows, for decades, women have been sidelined in nuclear policymaking. That makes our world less safe.

Exclusion in the national security world means ignoring those who may have more experience and knowledge about a region or population, the ability to foresee obstacles others are blind to and more potentially effective and innovative solutions. In the nuclear field, where the stakes are life and death on a massive scale, this exclusion is costly.

Although they may not have been prominent at the Trump-Kim negotiation, women have been integral to the nuclear diplomacy field from the beginning. Female scientists in the Manhattan Project held a range of positions, including physicists, chemists and phlebotomists, working with male researchers to study plutonium and troubleshoot nuclear reactors. As the nuclear arsenal expanded, so did the number of women working as translators, counsels and senior policy and national security advisers. Beginning in the 1970s, women served as under, assistant and deputy secretaries, and starting in 1993, as Cabinet-level secretaries in the State, Defense and Energy departments.

Yet, of everyone in a senior nuclear policy position in the U.S. government since the 1970s, including in an acting capacity, only 12 percent were women, 2 percent of whom were women of color. Even as women advanced on the diplomatic stage, structural and cultural barriers limited their opportunities and contributions. Until 1972, married women in the Foreign Service had to resign. Only in 1976 did military service academies admit women. In 1968 and 1976, Foreign Service officer Alison Palmer sued the State Department for gender discrimination. At that time, women received downgraded awards and performance reviews that mentioned gender and marital status, were typically assigned to consular work and “disproportionately [were] refused assignments as deputy chief of mission.”

Ideas about power — who has it and who doesn’t — also constrained women. Culturally, “male” traits, like speed, decisiveness and aggression, became seen as markers of successful power politics, instead of “feminine” traits such as deliberation, collaboration and negotiation. During the Cuban missile crisis, President John F. Kennedy’s assistant secretary of defense called his commander in chief a “pantywaist” for his caution. Military power has often had a quite literal connection to manhood: According to his United Nations ambassador, President Lyndon B. Johnson once pulled out his “organ” and cited it as the reason for involvement in Vietnam. These ideas continued into the 1980s, when suggesting restraint after a nuclear attack made someone a “wimp.”

Within the nuclear security field, then, a binary developed portraying opposition to nuclear weapons as feminine and policymaking as exclusively masculine. Inaccurate assumptions that women only supported peaceful policies like disarmament dominated, which women found frustrating. As one female policymaker working from the 1990s to today said, “We don’t soften policy by adding estrogen.”

This notion too often excluded women from diplomatic policy formation. But when women were given opportunities, they made significant contributions.

Consider trailblazers such as Ambassador Rozanne Ridgway, who was one of six women in her 1957 Foreign Service class. While she joined at a time when women were considered unsuitable for positions with “expert political knowledge or tough negotiating skills,” she ultimately led all of President Ronald Reagan’s nuclear negotiations with the Soviet Union and became the State Department’s third-highest-ranking official. Like many others, she credited her success to hard work and well-honed skills, but noted her unusual luck in having supportive male colleagues and a broad range of professional opportunities.

Despite Ridgway’s success, the field has still been unfriendly to women and diversity. Even as more women continued to join the nuclear workforce, they still found the culture unwelcoming, with rampant harassment and discrimination. Other forces — unpaid leave for pregnancy and family emergencies and a dearth of women in leadership positions — likewise affected women’s career paths.

In this light, our research, in which we interviewed 23 women, suggests that perhaps this field has remained the same despite major changes in our international system because the people working there have, too. Flournoy pointed to the “mini-me approach to mentoring,” whereby a senior person, often a man, decides to mentor and promote a younger man because “he reminds [him] of his younger self.” That, she said, is “going to be a self-perpetuating system.”

This has led to stagnant policy still based on deterrence theories developed during the 1940s. That staleness stems from what one of our interview subjects, former undersecretary of defense for policy Michele Flournoy called the “consensual straitjacket” of policymaking: how gendered expectations and pressures restricted innovation. Though the geopolitical conditions have changed, the culture still reflects the exclusive Cold War “nuclear priesthood” that values military experience and demands adherence to a specific range of theories.

As our interviewees repeatedly told us, it’s not that male policymakers are less innovative, creative or intelligent than their female colleagues; it’s that, if the field only values experts of a specific theoretical background and gender, the policy proposals will be just as narrow.

Negotiating successfully requires having the best people, regardless of gender, and recognizing that diversity enhances innovation. According to our interviewees and their decades of experience in the field, when a national security team includes staff with expertise in a range of topics, perspectives and personal experience, that team will be better able to see both threats and solutions to problems.

History has borne that out. President George H.W. Bush’s foreign policy team, which oversaw the end of the Cold War, included record-level concentrations of women in arms control and European affairs, including Heather Wilson as director of European Defense Policy and Arms Control and Condoleezza Rice as the Soviet and Eastern Europe Affairs adviser. Similarly, when Syrian chemical weapons were successfully destroyed at sea instead of on land in 2014, that idea originated from a woman-led team and was championed by a woman who persisted, despite pushback.

The story of women in nuclear security reflects many of the broader lessons we’ve learned about gender and politics: that women’s contributions have often been ignored or excluded, risking policies that lack key perspectives, nuance and debate. With today’s high stakes, we need national security policy that includes all of the best ideas. For that, history suggests we focus now on innovation, not preserving historical hierarchies.