The Jabhat al-Nusra’s April pledge of loyalty to al-Qaeda still looms large in discussions of Western backing of rebel fighters, and has obliged the US to go to great lengths to try to shift the conversation to backing certain rebels, potentially having them fight the other rebels.
That may play in soundbites, but the reality is al-Qaeda’s ties to Syrian rebels run deep. The group was backing al-Nusra virtually from the start, and that is still where their closest allies are, but other rebel blocs, particularly the foreign ones, see al-Qaeda at the very least as kindred spirits, if not outright allies.
The bulk of the rebellion’s front-line fighters are foreign Salafists or Nusra, meaning they are expected to do the heavy lifting in the ongoing civil war. The secularists, to the extent they fight at all, serve as auxiliaries to these fighters, and see common cause with them in fighting Assad, and by extension common cause with al-Qaeda.
The Obama Administration still has a vision of buying the loyalty of the secularist rebels away from the more Islamist portion of the rebellion. Buying them with weapons seems to be the working plan now, but in practice the rebel factions share their equipment back and forth out of sheer necessity, meaning the US support will inevitably be funneled around to the al-Qaeda-linked factions.