The U.N. Security Council on Wednesday unanimously approved a historic resolution aimed at ending the flow of foreign extremists to the world's conflicts. President Obama thanked the council but warned that "a resolution alone will not be enough." Julie Jacobson/AP hide caption

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A Syrian refugee boy stands outside his tent at Al Zaatri refugee camp in the Jordanian city of Mafraq, near the border with Syria, earlier this week. Muhammad Hamed/Reuters/Landov hide caption

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Secretary of State John Kerry urged European Union officials, including foreign policy chief Catherine Ashton, left, to support military action in Syria to punish the country for a chemical attack on its citizens. AFP/AFP/Getty Images hide caption

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