An early adversary of Assad, Turkey has firmly supported Syria's opposition, hosting its leaders and rebel commanders and retaliating against Syrian shells that have landed in its territory. Erdogan has been among the more vocal of the world leaders calling for a more hands-on U.S. effort, nudging Obama to act by declaring assertively that Syria has been delivering chemical weapons on hundreds of missiles — a move that would violate Obama's "red line" against chemical weapons use. Obama has said there's evidence of chemical weapons use but is holding off until the circumstances can be more definitively determined.
Erdogan, too, faces a public divided about the best way to confront the seething conflict in its backyard. Some Turks have accused their leader of putting the nation's security at risk by backing the rebels, prompting anti-government protests and calls for Erdogan to resign. Meanwhile, the 200,000 or so Syrian refugees along the border have stoked resentment among residents in the ethnically mixed regions of southern Turkey.
In an attempt to show concrete action, the Obama administration added four Syrian government ministers, a Syrian TV station and its national airline to a U.S. terror blacklist Thursday, blocking their U.S. assets and prohibiting Americans from doing business with them.
But even that step included a pointed reminder that the U.S. can't be sure who will claim power if and when Assad is ousted. In a parallel move, the State Department blacklisted Muhammad al-Jawlani, the leader of the al-Qaida-linked rebel group fighting Assad's regime. The State Department dubbed al-Jawlani as a "global terrorist" and said he aims to create an Islamist state in Syria.
Associated Press writer Bradley Klapper contributed to this report.
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