U.S. Chairman of the Joint Chiefs of Staff General Martin E. Dempsey prepares to testify before a Senate Armed Services Committee hearing on anti-IS strategy on Capitol Hill in Washington D.C., capital of the United States, July 7, 2015. U.S. defense chief said Tuesday that execution of the U.S. strategy against the extremist group, the Islamic State, fell short of expectation. (Xinhua/Bao Dandan)
