American soldiers Kris Kuntz (left) and Hayley Barner in Afghanistan, near the border with Pakistan, last October. Tauseef Mustafa /AFP/Getty Images hide caption

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The USS Carl Vinson, an aircraft carrier, near Hong Kong last month. Aaron Tam/AFP/Getty Images hide caption

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The Chinese People's Liberation Army (PLA) Air Force puts on an air display to mark its 60th birthday in Beijing on November 15, 2009. (Those are not stealth prototypes.) STR/AFP/Getty Images hide caption

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