Gen. Antonio Indjai (left), Guinea-Bissau's army chief of staff, at the funeral of the country's late president, Malam Bacai Sanha, on Jan. 15, 2012. The U.S. says Indjai has been involved in drug trafficking, an allegation he denies. He recently eluded a U.S. sting operation that led to the capture of other officials from his country. Mamadu Alfa Balde/AFP/Getty Images hide caption

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The White House said this week that it believes Syria has been using chemical weapons, but President Obama has not said how the U.S. might respond. Here, rebel fighters in Syria prepare to launch of a rocket in the northern Syrian city of Aleppo, on April 21. The rebels have also accused the Syrian government of employing chemical weapons. Miguel Medina /AFP/Getty Images hide caption

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First responders aid injured people at the finish line of the Boston Marathon after the bombing on April 15. Charles Krupa/AP hide caption

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Sen. Rand Paul, R-Ky., attends a ceremony for Time's "100 Most Influential People in the World" in New York on Tuesday. Evan Agostini/Invision/AP hide caption

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