Katie Gorz (left) performs the ammo can lift next to male Marines as they go through the combat fitness test. The Marine Corps is experimenting with inserting some women into combat infantry roles that have historically been limited to men. At Camp Lejeune, female Marines are undergoing the same training as their male counterparts for combat arms. Travis Dove for NPR hide caption

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Women in the U.S. military will be integrated into front-line combat units by 2016, the Pentagon says. Here, female Marine recruits stand in formation during pugil stick training in boot camp earlier this year at Parris Island, S.C. Scott Olson/Getty Images hide caption

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Female soldiers from 1st Brigade Combat Team, 101st Airborne Division train on a firing range in Fort Campbell, Ky., in preparation for their deployment to Afghanistan. The Pentagon announced Thursday that women will no longer be banned from combat roles. Mark Humphrey/AP hide caption

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Hospital Corpsman Shannon Crowley, with a Marine Corps. Female Engagement Team, in Musa Qala, Afghanistan, in November 2010. Paula Bronstein/Getty Images hide caption

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Republican presidential candidate Rick Santorum in McKinney, Texas, on Wednesday. Tom Pennington/Getty Images hide caption

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