FILE - In this Tuesday, June 12, 2012 file photo, a Syrian revolutionary flag waves on top of a building on the outskirts of Aleppo, Syria. Syria's conflict is the most violent to emerge from last year's Arab Spring. The protests started peacefully but prompted a brutal crackdown by President Bashar Assad's government. The fighting has escalated into a civil war that has killed just over 30,000 people over the last year and a half, according to activists. Despite intervening in Libya, the United States has steered clear of taking military action or arming Syria's rebels. (AP Photo/Khalil Hamra, File)

Photo by: Khalil Hamra

FILE - In this Tuesday, June 12, 2012 file photo, a Syrian revolutionary flag waves on top of a building on the outskirts of Aleppo, Syria. Syria's conflict is the most violent to emerge from last year's Arab Spring. The protests started peacefully but prompted a brutal crackdown by President Bashar Assad's government. The fighting has escalated into a civil war that has killed just over 30,000 people over the last year and a half, according to activists. Despite intervening in Libya, the United States has steered clear of taking military action or arming Syria's rebels. (AP Photo/Khalil Hamra, File)