U.S. Secretary of Defense Chuck Hagel pauses during a media briefing at the Pentagon in Washington, August 21, 2014. The sophistication, wealth and military might of Islamic State militants represent ... more 
U.S. Secretary of Defense Chuck Hagel pauses during a media briefing at the Pentagon in Washington, August 21, 2014. The sophistication, wealth and military might of Islamic State militants represent a major threat to the United States that may surpass that once posed by al Qaeda, U.S. military leaders said on Thursday. REUTERS/Yuri Gripas (UNITED STATES - Tags: POLITICS MILITARY CONFLICT CIVIL UNREST) less 
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Reuters | Photo By YURI GRIPAS / REUTERS
Thu, Aug 21, 2014 7:44 PM EDT