The United States has had 77 secretaries of the treasury, 27 secretaries of defense and 25 directors of intelligence.

All 135 of these roles have been filled by men.

Women are poised to fill at least two of these positions in President-elect Joe Biden’s incoming administration. If confirmed, Avril Haines will be the first woman to lead the U.S. intelligence community. Biden is expected to name Janet L. Yellen — the first chairwoman of the Federal Reserve — as the first female secretary of the treasury. There is speculation that Biden might also pick a woman for the country’s top defense job, an announcement likely to come later this week.

There have been plenty of female Cabinet members, starting with Frances Perkins, who served in President Franklin D. Roosevelt’s administration as the head of the department of labor from 1933 to 1945. But in the 87 years since Perkins joined the Cabinet, a few key positions have remained off-limits to women. If they are confirmed, Yellen and Haines will break through glass ceilings in two of the most important divisions of the federal government.

The secretaries of treasury and defense, in particular, are among the most powerful positions in the Cabinet, widely regarded as two of the “Big Three,” a group that also includes the secretary of state, a role that has been held by three women. These three positions typically hold the most authority, garner the most media attention and best position their occupants for higher office, write politics professors Mona Krook and Diana O’Brien in their paper, “All the President’s Men?”

“Treasury is markets and defense is war — and that is the inner sanctum of male power,” said Anne-Marie Slaughter, former director of policy planning for the U.S. State Department under Hillary Clinton and chief executive of New America, a public policy think tank. It’s a “big deal,” she says, that women are finally breaking through.

Biden has said he intends to appoint a Cabinet “that will look like America,” following other countries around the world that have pledged to maintain a “parity cabinet,” reflecting their population’s gender and racial demographics. Biden is in a unique position to appoint a historically diverse group, Slaughter says. Had Clinton won in 2016, Slaughter says, she probably would have been somewhat hamstrung by her gender, under pressure to follow traditional Cabinet conventions.

“Biden doesn’t have to worry about any of that,” Slaughter says. “He is himself an older White man, so he can break these barriers.”

There has been no “linear path” toward gender parity in the U.S. Cabinet, says Maria Escobar-Lemmon, a professor of politics at Texas A&M University. Progress has looked more like a swinging “pendulum,” she says: One administration will appoint a significant number of women to high-ranking positions, while the next one will appoint fewer. Republican presidents typically appoint fewer women to the top jobs than Democrats, Escobar-Lemmon says.

Before President Trump, a woman or a minority had held a top Cabinet position — any of the Big Three or attorney general — since President Bill Clinton appointed Madeleine K. Albright in 1997 as the first female secretary of state. Trump selected four White men for those top roles after he was elected in 2016. Multiple people held each of these positions throughout his four years in office.

All of them were men.

“I would look at Trump’s meetings and ask myself, ‘Is that the Cuban missile crisis?’ ” Slaughter said. Trump’s Cabinet looked like the “1960s,” she said. “There were so many White men.”

While Trump’s Cabinet included far fewer women than his predecessors, even President Barack Obama’s Cabinet did not come close to reaching gender parity, said Krook, a professor at Rutgers University: Women made up 32 percent of his original Cabinet in 2008, which included Hillary Clinton as secretary of state.

Of the Big Three, it’s not surprising that women have been selected, three times over, to lead the State Department.

“Diplomacy is often seen as more feminine,” Krook said. “It’s consensus-building, talking, negotiating.” Treasury and defense, on the other hand, are seen as “quintessential masculine pursuits.”

Over the years, it’s been partially a “pipeline problem,” Krook said. Secretaries of defense are typically selected from the highest echelons of the military, or agencies connected with the military, she says, all of which are dominated by men. The same goes for secretaries of the treasury, often selected from a shortlist of esteemed economists or Fortune 500 chief executives.

But it’s not that simple, Escobar-Lemmon said. For decades, she said, there have been women who could have filled these positions — but they may not have been part of the president’s most trusted inner circle. The top Cabinet members are often selected for their trustworthiness and their perceived loyalty, she said, which benefits White men.

“You’re looking for someone you know you can trust, but women have not been in the room for years,” Escobar-Lemmon said. “So it becomes, ‘Oh yes, she’s qualified, but I don’t know her.’ ”

“For all these jobs, we could all list off a few women who are just as qualified as any man,” Slaughter says.

Other countries have not been so slow to change. Many European and Latin American countries have had women leading their budget and defense departments. Photos of Spanish Defense Minister Charme Chacón went viral in 2008: She was inspecting the troops while she was seven months pregnant.

Canadian Prime Minister Justin Trudeau made headlines for choosing women to fill 50 percent of his Cabinet positions after he was elected. When asked why, he famously said, “Because it’s 2015.”

There will almost certainly be increased scrutiny on Yellen, Haines and any other women Biden selects to fill roles that historically have gone to men, Escobar-Lemmon said. People will want confirmation that their credentials line up with the men who have held the positions in the past.

Their appointments will open doors for young women working their way up in their industries, Slaughter said. It’s no surprise, she said, that two other women — Clinton and Condoleezza Rice — quickly succeeded Albright as secretary of state.

“Part of the pipeline issue is women not being able to imagine themselves in these positions,” Slaughter said.

Now they can.

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