Gen. Stanley McChrystal during a retirement ceremony in 2010. His comments in a Rolling Stone interview helped lead to his resignation. Brendan Smialowski/Getty Images hide caption

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Chuck Hagel, President Obama's nominee for defense secretary, testifies before the Senate Armed Services Committee during his confirmation hearing on Jan. 31. Susan Walsh/AP hide caption

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Gen. David Petraeus is the subject of The Insurgents: David Petraeus and the Plot to Change the American Way of War, a new book by Fred Kaplan. Shah Marai/AFP/Getty Images hide caption

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President Obama nominates former Sen. Chuck Hagel, R-Neb., to be defense secretary Monday at the White House. Mark Wilson/Getty Images hide caption

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Marilyn Gonzalez (left) and her daughter, Jessica Pedraza, at their base in Kuwait in 2010. Courtesy of Jessica Pedraza hide caption

itoggle caption Courtesy of Jessica Pedraza

Col. Eric Schwartz (left), Dr. Najeeb Hanoudi (center) and Maj. Ron Cooper outside Hanoudi's home in Southfield, Mich. Emily Fox hide caption

itoggle caption Emily Fox