Abdel Bari Atwan, is a Arab newspaper editor based in London, has a short article and is pungent in his criticism:https://www.opendemocracy.net/arab-a...%80%99t-get-it

Here is an early sample:
It is obvious to me that IS is a very different—and infinitely more dangerous—creature than any of its predecessors, al-Qaeda included.....IS has not sprung from nowhere. It is the latest evolutionary step in the Salafi-jihadi movement, specifically the global jihadi, anti-American tendency introduced by Osama bin Laden and Ayman al-Zawahiri in 1996.
He is very pessimistic:
The best hope lies in the most powerful jihadi entities—al-Qaeda, the Taliban and IS—fighting and destroying each other.
Alas there is little sign that this will happen:
Failing violent implosion, only a long term, carefully thought out, and region-wide strategy could work. A concerted effort by the region’s policy-makers and influencers to introduce and nurture values of tolerance, unity, mutual co-operation and peace would have a good chance of ousting IS... because hatred, anger and resentment are the oxygen it needs to flourish.