(DoD photo by Cherie Cullen/Released)
Christine Fox sits at left. (DoD photo by Cherie Cullen/Released)

President Obama has named Christine Fox, formerly the Pentagon's chief budget and program analyst, as the country's acting deputy defense secretary until a permanent replacement is found. The move is "unprecedented," the Military Times reports, both because of the rarity of naming an acting deputy secretary and because the move will make her the highest ranking woman to ever serve in the Department of Defense. She'll assume the post when current deputy defense secretary Ash Carter, who is retiring, steps down on Wednesday.

Her position may not be permanent, but it is a critical one. In a profile of Defense Secretary Chuck Hagel published earlier this week, Politico Magazine wrote that because of Hagel's relative newness to the Pentagon, replacing the "highly regarded" Carter with someone with extensive experience at the Pentagon is "a first-class necessity." And in announcing the move, the American Forces Press Service wrote that her appointment comes at a "pivotal moment," allowing the current management team to stay in place until a permanent successor is found.

As an acting director, the Military Times reports, Fox will be able to serve in an acting capacity for 210 days; once a permanent nomination is made, she could serve indefinitely. She will not be in the line of succession but will otherwise maintain the rights and responsibilities of the position.

Fox returns after leaving the Pentagon in June, where she had served as the director of Cost Assessment and Program Evaluation (CAPE) for four years, and worked closely with Hagel on the Pentagon's Strategic Choices and Management Review. Formerly, she was the president of the Center for Naval Analyses, a Naval think tank, and the scientific analyst to the Chief of Naval Operations. Her bio states that she has served as a member of NASA's Return to Flight Task Group and was a member of the Applied Physics Laboratory's Advisory Board. Since leaving the Pentagon earlier this year, she has been a senior adviser to the Johns Hopkins Applied Physics Laboratory and remained an unpaid consultant to Carter, Military Times reports.

In addition to those distinctions, Fox holds another, er, claim to fame. The new acting deputy defense secretary, who was an analyst at the real Top Gun school in the 1980s while working as a civilian employee for CNA, is also the inspiration for the Kelly McGillis character in the movie "Top Gun." A People magazine profile from 1985 says that the producers originally considered making Tom Cruise's love interest a gymnast or a groupie, but settled on an astrophysicist named "Charlie" after an admiral introduced Fox to the movie's producers. (Fox holds degrees in mathematics and applied mathematics.)

The People article reports that Fox is 6 feet tall, was encouraged to study math by her father, a naval nuclear engineer, and at the time was the only woman working in the field for CNA. Women were so absent from the Miramar campus back then that she was sometimes asked by guards whether she was there to pick up her husband's check. A window into the gender views and casual sexism of the era, the feature piece quotes one naval captain as saying "she's the smartest woman I've ever met. I like women for a lot of things and being smart isn't usually one of them." What a difference 28 years makes.

Jena McGregor is a columnist for On Leadership.

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