The renowned Syrian Scholar Shaykh Mohammad Al-Yaqoubi mentions a significant point. That these extreme fringes have always existed in Islam but now they have been given a stage or have been empowered.

We know ISIS is no different to the Khawarijites that existed during the time of Mohammad(SAW) but they were always a power hungry minority whos forces were always thwarted by the Muslim majority. What we are seeing now is what happens when these fools are empowered and corrupt Muslim leaders (Saudi) aren't solely to blame for this but corrupt leaders of the West also.

Interview here:
https://www.youtube.com/watch?v=yjT107O6uBQ


Related:

Profiles of Syrian Sunni Clerics in the Uprising:
http://carnegieendowment.org/syriain...4&reloadFlag=1

ISIS a monster created by Saudi and Western Government:
A picture that speaks more than a thousand words...