In preparing the public for a disaster, officials want to make the right call, but they also want to avoid blame. Win McNamee/Getty Images hide caption

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Libyans wave national flags in Tripoli's Green Square, renamed Martyr's Square, during morning prayers Wednesday on Eid al-Fitr, the holiday marking the end of Ramadan. Libyans are also celebrating the ouster of Moammar Gadhafi. Francois Mori/AP hide caption

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A camera is mounted on a building near Temple University in Philadelphia. Humberto Fernandini, with the company that owns the building, says the owners plan to register their cameras for the police department's new program. Elizabeth Fiedler for NPR hide caption

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Republican presidential candidate and Texas congressman Ron Paul at Iowa State University in Ames on Aug. 13, 2011. Scott Olson/Getty Images hide caption

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A Liberian immigrant picks African peppers on the Bowling family farm in Charles County, Md. It's one of a handful of farms experimenting with growing African produce to cater to the D.C. region's large African immigrant community. Marina Dominguez/NPR hide caption

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This June 2, 2010, file photo shows the AT&T logo in Washington, D.C. The U.S. Justice Department will seek to block AT&T's proposed $39 billion acquisition of T-Mobile. Etienne Franchi/AFP/Getty Images hide caption

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Deputy Defense Secretary William Lynn (left) presents Gen. David Petraeus with an American flag at his retirement ceremony after 37 years in the Army, in Arlington, Va., on Wednesday. Petraeus will now lead the CIA. Saul Loeb/AFP/Getty Images hide caption

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