The terrible twitter machine? I guess nobody. But who cares.
As for who is able to stop ISIS - pretty much any country who cares to could individually if they turned their full attention to it. As is, the coalition has made fantastic progress and ISIS's progress has stalled and will soon be peeled back. They've been exposed. An entity like that is either expanding or dying. They're dying.
Edit: see my posts in this thread for a more fulsome discussion of the variety of ways in which ISIS is inadequate and getting their collective ass kicked.
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