Turkey apparently wants the Kurds defeated, and so is willing to stand by and let ISIS do the job.
After which, Turkey may—or may not—move in to pick up the pieces.
But in the meantime, Turkey must appear as the “ally” of the Kurds, and call for international support (which it knows will not be forthcoming).
ISIS is Qatar (cash) + Turkey (everything else).
Why would Turkey kill what it has birthed?
That’s because Turkey SUPPORTS ISIS.
And Turkey is part of NATO?