Disbelievers (Qafir or non muslims) were indeed being eliminated as says in the Quran once upon a time ago. But modern Islam movement discourage that for the sake of respect in humanity. ISIS however believe in conservative Islam. Ancient Islam battle with Christian and those who pray to other than Allah despite of anything happen between Islam and other religions at the first place. It was the practice back on those years but now no more.

Well somehow...those days are coming back slowly..Our Malaysian muslims have slowly becoming more racist in religion and extremist too. Social medias are now flooded with religious personnels that gain popularity.....and now ISIS. If you can see more malaysian muslims ladies wearing hijab right, you shud see british muslims ladies....they are all going Burka recently.