FSA officials have suggested that the struggle with the Islamic Front might be resolved through negotiations, and that U.S. shipments might eventually resume. But speculation is already swirling that the FSA and its leadership under Gen. Salim Idriss — officially called the Supreme Military Command, or SMC, the political opposition’s military wing — might be at its end. One source close to the SMC called the Islamic Front’s recent aggression in Atimeh “an attack and overthrow, basically.”…

Recent events raise a critical question for the FSA. If it can’t secure its supply routes into Syria from Turkey, its most important base for international support, how can it survive? The FSA is also bleeding fighters to its more Islamist counterparts; several key battalions bolted for the Islamic Front last month. “You’ve got to ask: What does Selim Idriss control right now?” said Michael Stephens, the deputy director of the Royal United Services Institute in Qatar. “How does he get supplies and weapons to his fighters? And how is he going to get this stuff across the border without Islamic Front or one of the more extreme groups taking a cut? And the answer is he can’t. This was almost like an internal coup.”

The Islamic Front has received significant backing from Gulf countries. It says it want to establish an Islamic state in Syria, governed by Sharia Law — a far cry from the secular, democratic platform espoused by the SMC and main political opposition backed by the U.S. and its western allies. But while the Islamic Front is on the upswing, the FSA has been withering for months as its leaders plead for more meaningful support. “I think Western opposition policy is collapsing,” Stephens said.