An image grab taken from Egyptian state television shows Egyptian President Hosni Mubarak (left) speaking with his new Vice President Omar Suleiman (center) and Chief of Staff Sami Anan during a visit to the military operations center in Cairo on Sunday. AFP/Getty Images hide caption

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President Obama and first lady Michelle Obama greet Chinese President Hu Jintao at the state dinner at the White House on Wednesday. Hu's red carpet treatment in Washington this week underscores his country's status as the top U.S. economic rival. Carolyn Kaster/AP hide caption

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Vice President Joseph Biden welcomes Chinese President Hu Jintao to Andrews Air Force Base on Tuesday. Analysts say the Chinese leader's visit could be among the most pivotal in U.S. history. Hu meets with President Obama on Wednesday. Mark Wilson/Getty Images hide caption

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A massive 2007 cyberassault, traced to Russia, highlighted the need for Estonia to set up a Cyber Defense League, a force of programmers, computer scientists and software engineers who in wartime would function under a unified military command. iStockphoto hide caption

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WikiLeaks supporters gather in front of the United States Federal Building in New York City on Thursday. Spencer Platt/Getty Images hide caption

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Mark Stephens, lawyer for WikiLeaks founder Julian Assange, talks to the media as he leaves a court hearing for his client in London. Assange was jailed after telling the court he will fight efforts to extradite him to Sweden, where he faces a sex-crimes investigation. Sang Tan/AP hide caption

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A leaked cable from a U.S. diplomat suggests that a cyberattack on Google's China operations was ordered by the highest level of the Beijing government. Franko Lee/Getty Images hide caption

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Marines on patrol in Afghanistan's Helmand province walk near a blast crater from a homemade explosive device. Roadside bombs are the leading killer of U.S. troops in Iraq and Afghanistan. The American military has turned to mathematics and social network analysis to help identify bombers and their supporters. David Gilkey/NPR hide caption

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Leaders from the Group of 20 nations smile for the cameras on Friday, but this year's summit wasn't as productive as the ones that preceded it. Getty Images hide caption

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