Sgt. 1st Class Joseph Denny of Franklin, Ind., trades headgear with an Afghan boy during a June 6 patrol in a village south of Kandahar. When Gen. David Petraeus takes command in Afghanistan, he will inherit unfinished military operations in Kandahar and Marjah. Chris Hondros/Getty Images hide caption

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Night turned into day on July 9, 1962, when the U.S. government exploded a hydrogen bomb 1,000 times more powerful than the bomb that hit Hiroshima above Earth's atmosphere. This is a sunset you don't ever want to see. Terry Luke/Honolulu Star-Advertiser hide caption

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U.S. Army armored vehicles leave their base on May 28 after a handover ceremony northeast of Baghdad. The U.S. plans to have just 50,000 troops in Iraq by Aug. 31. But many Iraqis say the country the U.S. is leaving behind is hardly a success story. Karim Kadim/AP hide caption

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Chester Reed, 95, moves postal crates at a distribution center in Redlands, Calif. He retired Wednesday as the nation's oldest postal worker. Nick Ut/AP hide caption

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Mark Diaz, manager of Schrank's Smoke 'n Gun shop, displayed several handguns for sale at the store last year in Waukegan, Ill., north of Chicago. When the Supreme Court ruled Monday that most Americans can have a handgun in their homes for self-defense, it left Chicago officials scrambling to put together a new handgun law. M. Spencer Green/AP hide caption

itoggle caption M. Spencer Green/AP