Today's anti-Assad rebel is tomorrow's ISIS, there are no real "sides" in non-state conflicts, only self preservation that allies with the position of local strength. If one were totally devoid of humanitarian concern, the creation of a common enemy would be the only way to ally traditional enemies. The plausibility of the strategy is there. But I think the most hardened CIA warrior could foresee the misery.
There is but I don't think he is respected outside the delusional no knowledge homers and even those kool aiders think he is a nitwit