U.S. soldiers stand at a checkpoint around Lakokhel camp in Afghanistan in 2010. Many soldiers return from war suffering from "moral injuries," or dealing with the fact that their sense of right and wrong was violated. Martin Bureau/AFP/Getty Images hide caption

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Gen. John F. Campbell, the top U.S. commander in Afghanistan, speaks during a ceremony in Kabul on Aug. 26. Campbell is overseeing the U.S. drawdown in the country after 13 years of war. Massoud Hossaini/AP hide caption

itoggle caption Massoud Hossaini/AP

Four Americans injured in Iraq and Afghanistan visit Kabul as part of Operation Proper Exit, a program designed for wounded warriors. From left, they are Staff Sgt. Ben Dellinger, Capt. Casey Wolfe, Capt. John Urquhart (who is hidden) and Sgt. James "Eddie" Wright. Sean Carberry/NPR hide caption

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U.S. Marines board a C-130 transport plane as they withdraw from Camp Leatherneck, their huge base in southern Afghanistan. This marked the biggest handover yet to the Afghan army, which is facing a tough fight with the Taliban in Helmand province and other parts of southern Afghanistan. Wakil Koshar/AFP/Getty Images hide caption

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U.K. armed forces and U.S. Marines have ended combat operations in Afghanistan. In a formal handover, British troops stood with peers from the U.S. Marine Corps and the Afghan National Security Forces as the Union Flag and Stars and Stripes were lowered for the last time at the Bastion-Leatherneck complex Sunday. Sergeant Obi Igbo, RLC/AP hide caption

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Afghan National Security Adviser Mohammad Hanif Atmar (right) and U.S. Ambassador to Afghanistan James Cunningham exchange documents after signing the Bilateral Security Agreement, with Afghan President Ashraf Ghani (rear, left) and Chief Executive Abdullah Abdullah in the background. Jawad Jalali/EPA/Landov hide caption

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Ashraf Ghani (second from left) stands next to Afghanistan's Chief Executive Abdullah Abdullah (left) and two deputy officials as he takes the oath during the inauguration ceremony at the presidential palace in Kabul on Monday. Ahmad Massoud/Xinhua/Landov hide caption

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Afghan presidential candidates Abdullah Abdullah, left, and Ashraf Ghani Ahmadzai shake hands after signing a power-sharing pact in Kabul Sunday. The first vote in the election was held in April; a runoff followed in June. Wakil Kohsar/AFP/Getty Images hide caption

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