The gray line in the upper left comes from an aerial view of Afghanistan's crucial Highway 1, the main route between Kabul and Kandahar, the two biggest cities. U.S. forces are still working to secure the route which runs through lush farm valleys and the high desert terrain. David Gilkey/NPR hide caption

itoggle caption David Gilkey/NPR

U.S. Army Sgt. Michael Johnson trains at Bagram Air Field for the Memorial Day Murphy, a CrossFit workout honoring a Navy SEAL killed in Afghanistan in 2005. David Gilkey/NPR hide caption

itoggle caption David Gilkey/NPR

Marine Sgt. Maj. Damion Jacobs (left) and Marine Capt. Cam West visit with Boston emergency workers who responded to the bombings at the Boston Marathon. Oren Dorell for USA Today hide caption

itoggle caption Oren Dorell for USA Today

Gen. Antonio Indjai (left), Guinea-Bissau's army chief of staff, at the funeral of the country's late president, Malam Bacai Sanha, on Jan. 15, 2012. The U.S. says Indjai has been involved in drug trafficking, an allegation he denies. He recently eluded a U.S. sting operation that led to the capture of other officials from his country. Mamadu Alfa Balde/AFP/Getty Images hide caption

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Defense Secretary Chuck Hagel speaks wednesday at the National Defense University at Fort McNair in Washington, D.C. He warned of deep budget cuts across his department, to put the brakes on spiraling costs and reshape the military for leaner budgets and new challenges. Manuel Balce Ceneta/AP hide caption

itoggle caption Manuel Balce Ceneta/AP

Army recruits perform exercises as part of a demonstration for tourists in front of the military-recruiting station in New York's Times Square. Mark Lennihan/AP hide caption

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The winding down of the war in Afghanistan and efforts to slice the budget deficit will likely mean more spending cuts for the Pentagon. AFP/Getty Images hide caption

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Gen. Carter Ham, who heads the U.S. Africa Command, meets with Algerian President Abdelaziz Bouteflika last September. Amid upheaval in the region, AFRICOM is still attempting to define its mission. Farouk Batiche/Getty Images hide caption

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Gen. Carter Ham is head of the U.S. African command. An Army brigade from Fort Riley, Kan., will begin helping train African militaries beat back a growing terrorist threat posed by al-Qaida. AP hide caption

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Sen. Chuck Hagel, R-Neb., and then-presidential candidate Barack Obama in Amman, Jordan, in 2008. Paul J. Richards/AFP/Getty Images hide caption

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USS Enterprise sails in the Persian Gulf while in support of Operation Southern Watch and the extended "no-fly" zone over Iraq on Sept. 22, 1996. Matthew Hostetler/AP hide caption

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