Afghan commandos work on clearing a mock house during a training session conducted by the U.S. Army Special Forces at Fire Base Thomas in western Afghanistan. David Gilkey/NPR hide caption

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Afghan President Hamid Karzai (center right) speaks to locals during a gathering in Kandahar on April 4. Karzai has expressed his desire to negotiate with the Taliban and other militants. But a conference on national reconciliation was postponed until the Afghan president confers next month with President Obama at the White House. Golnar Motevalli/AFP/Getty Images hide caption

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Afghan protesters shout anti-American slogans during a protest in Kandahar, Afghanistan, on April 12 after international troops opened fire on a bus carrying Afghan civilians, killing at least five people. Allauddin Khan/AP hide caption

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Lance Cpl. Chris Garcia and other members of Golf Company cross an irrigation ditch as the 2nd Battalion, 8th Marine Regiment moves into Helmand province in July during a major offensive against the Taliban stronghold in southern Afghanistan. David Gilkey/NPR hide caption

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An Army Honor Guard prepares to carry the flag-draped coffin of Staff Sgt. Vernon Martin into St. John's Baptist Church for his funeral service on Oct. 19, 2009, in Savannah, Ga. Martin, 25, was one of eight U.S. soldiers killed Oct. 3 during a fierce battle at Combat Outpost Keating in Afghanistan. Stephen Morton/Getty Images hide caption

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Afghan President Hamid Karzai (center), surrounded by bodyguards, walks through Kandahar city, south of Kabul, earlier this month. The purpose of the president's visit was to consult with and seek the support of locals for an upcoming U.S. and NATO military campaign there to drive out the Taliban. But the operation is meeting resistance. Allauddin Khan/AP hide caption

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President Obama walks with Afghan President Hamid Karzai at the presidential palace in Kabul on March 28. In recent comments, Karzai has blamed the West for many of his troubles, causing concern in Washington. Charles Dharapak/AP hide caption

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Afghan motorists pass a U.S. soldier on patrol last month in Afghanistan's southern Kandahar province. U.S. and Canadian forces have announced a major upcoming offensive against the Taliban in Kandahar, the group's stronghold and spiritual birthplace. John Moore/Getty Images hide caption

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