US policy in Syria is based on the fiction that a "moderate" armed opposition exists which is separate from al-Nusra (al-Qa'ida).

Obama and his top staff must know this. What I don't see is what they hope to achieve. Convert part of al-Qa'ida into a US ally? It might not be a ridiculous idea, given that nearly all sides in Syria have committed great crimes (the exception being the Kurds). But if we can forgive al-Qa'ida its crimes, why not Assad too?