In Istanbul on Saturday, Syrian National Coalition President Ahmad Jarba announces the opposition group will attend the upcoming peace conference in Geneva. AFP/Getty Images hide caption

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The flag of the Islamic State of Iraq and Syria, or ISIS, flutters on the dome of an Armenian Catholic Church in the northern rebel-held Syrian city of Raqqa on Sept. 28, 2013. At first, Syrian rebels and civilians welcomed the experienced Islamist fighters, and the groups fought together to take over the city from Syrian troops. Now, many Syrians fear and resent ISIS. AFP/Getty Images hide caption

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