isil are islamites and there are always new groups forming causing seemingly endless instability. The Khmer Rouge was awful but it was a rare travesty and Pol Pot had some really weird views. For example he himself claimed he wasn't even a communist, but a 'revolutionary'. He also had some posadist elements. He was a maniac responsible for well over 1 million deaths. ISIL doesn't even come close, although the ideas which spawn such movements should be considered as equally degenerate because the islamite crisis is an ongoing one so it is difficult to measure how many people exactly will be killed by such organisations in the middle east (if and when this all ends).
