First of all call them Jihadi terrorists. This seed of terrorism was planted 1400 yrs ago. Google out who killed innocent members of tribes like Banu Quraiza and Banu Nadr and forcibly took away their women and children? Ask who forcibly married Maria, the Jewish woman, after killing her husband and father in front of her own eyes? Ask who waged relentless war for last 1200 yrs on India and forcibly converted lakhs of people to Arabian cult? Only then will you recognize the root cause of terrorism.