"Today's anti-Westernism is a reaction to yesterday's racism," Iranian President Hassan Rouhani said in a speech at the U.N. General Assembly on Thursday. Jason DeCrow/AP hide caption

itoggle caption Jason DeCrow/AP

Fighters from the Islamic State group parade in their northern Syrian stronghold, Raqqa. Uncredited/AP/Raqqa Media Center hide caption

itoggle caption Uncredited/AP/Raqqa Media Center

In this image made through a window of the Oval Office, President Obama speaks on the phone to Saudi Arabia's King Abdullah on Wednesday. Charles Dharapak/AP hide caption

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Staff Sgt. Daniel Leavindofske and Senior Airman David Babcock help load bundles of halal meals onto a cargo aircraft for a humanitarian mission over Iraq on Saturday. Staff Sgt. Vernon Young Jr./U.S. Air Force via Getty Images hide caption

itoggle caption Staff Sgt. Vernon Young Jr./U.S. Air Force via Getty Images

People walk on the rubble of the destroyed Mosque of the Prophet Yunus, or Jonah, in Mosul. The revered Muslim shrine was destroyed on Thursday by militants who overran the city in June and imposed their harsh interpretation of Islamic law. Uncredited/AP hide caption

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Iraqi Shiite volunteers with the Labayk ya Hussein Brigade take part in a training session in the holy city of Najaf in late June. Clerics in the city called for Shiites to step forward and fight the Sunni group formerly known as the Islamic State of Iraq and Syria (which now calls itself simply the Islamic State). Haidar Hamdan/AFP/Getty Images hide caption

itoggle caption Haidar Hamdan/AFP/Getty Images