Former CIA director and retired Gen. David Petraeus during his address Tuesday at the University of Southern California. Frederic J. Brown /AFP/Getty Images hide caption

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Then-CIA Director David Petraeus testifies on worldwide threats before the Senate Select Committee on Intelligence, on Jan. 31. Zhang Jun/Xinhua /Landov hide caption

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Then-Gen. David Petraeus in mid-2011, just before he became CIA director. Barbara Sax/AFP/Getty Images hide caption

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Gen. David Petraeus in Kandahar, Afghanistan, on July 4, 2011. U.S. Navy Lt. j.g. Haraz N. Ghanbari/Getty Images hide caption

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