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

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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

itoggle caption Jawad Jalali/EPA/Landov

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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Abdullah Abullah (left) and Ashraf Ghani, shown here on August 8, have been contesting the results of Afghanistan's runoff presidential election for months. They are expected to sign a power-sharing deal on Sunday. Wakil Kohsar/AFP/Getty Images hide caption

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Nicaragua's Contra rebels in 1990. The U.S. backed the Contras in the 1980s, which led to the ouster of the leftist Sandinista leadership. But the U.S. aid violated American law and contributed to the biggest scandal of President Reagan's administration. Michael Stravato/AP hide caption

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An Afghan firefighter emerges from the smoke from a fire in a Kabul clothing market in 2012. The fire department is remarkably professional in a city where few institutions function. Mohammad Ismail/Reuters /Landov hide caption

itoggle caption Mohammad Ismail/Reuters /Landov

Many Afghans who have worked as interpreters with the U.S. and other Western governments are trying to get visas to leave. "Mohammad," an interpreter, joined two former British soldiers last year in that country to call on Britain to grant Afghan interpreters asylum. Kirsty Wigglesworth/AP hide caption

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An Afghan policeman searches a man at a checkpoint where a NATO soldier was stabbed to death in Kabul on Aug. 20. As U.S. and NATO troops are drawing down in Afghanistan, the Taliban have been stepping up attacks this summer. Shah Marai/AFP/Getty Images hide caption

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Secretary of State John Kerry and Afghanistan's presidential candidates, Ashraf Ghani (center) and Abdullah Abdullah (right), announce a deal in Kabul on July 12 to audit all Afghan election votes. Kerry returned last week and both candidates reaffirmed their commitment to the audit. Jim Bourg/AP hide caption

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