So we know that Saudi Arabia and Turkey are supporting all Islamist groups (yes, including ISIS) for the strategic purpose of overthrowing Assad, poking Iran in the eye, and putting Syria in the Sunni camp.
We also know the USA/Obama supports the overthrow of Assad, to give Putin a black eye, and presumably to have a Saudi-backed regime that is more pliable to US interests.
We also know that Erdogan in Turkey is using the flow of refugees as blackmail and a bargaining chip against Europe and for money $$.
And we also know that *any* effort in that part of the world carried out by the current occupant of the WH and his staff will be grossly bungled to the extent that some subsequent effort and inevitably some subsequent-subsequent effort after that will be required. And that too will fail.