U.S. Marines take cover as they are involved in a gun battle in March during a patrol in Marjah, Afghanistan. In February, U.S.-led troops set out to rid the area of insurgents and set up a viable local government. But Taliban militants have returned to the area. Dusan Vranic/AP hide caption

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Pro-Palestinian demonstrators wave Turkish and Palestinian flags during a protest Sunday in Ankara against Israel's deadly raid on a Gaza-bound aid ship. The attack was the latest blow to U.S.-Turkish relations. Adem Altan/AFP/Getty Images hide caption

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Gen. Stanley McChrystal (left), commander of NATO forces in Afghanistan, speaks with Central Intelligence Agency Director Leon Panetta during a meeting between U.S. and Afghan delegations at the State Department in Washington, D.C., earlier this month. Scott Applewhite/AP 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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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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