Syria under Bashir Assad (closed end 2014)

[Dayuhan]

Agreed. Outside assistance at this point probably counts for 5% or less of rebel resources, although it is starting to increase.

Sending weapons is of no use if there are no fighters willing or able to use the weapons... material aid can assist a rebellion, but it can't create one. I suspect that ultimately Assad's fate will depend on his ability to retain the loyalty of his armed forces, not on any outside involvement.

It might be claimed that outside introduction of certain weapons could be decisive in an insurgency. That claim has sometimes been made for the US introduction of MANPADS during the Soviet-Afghan war, though that claim has been credibly challenged. I've seen no suggestion that any such game-changing weaponry has been introduced in Syria.

The "civil war vs proxy war" dichotomy that people throw around is an odd one

Odd, but useful: there's always propaganda value, for either side, in claiming that your opponent is a tool of the manipulative furriner.