The reason is simple
Their religion dictates that WE must die! They are on a holy jihad to exterminate all non Muslims, and many Muslims who don't follow them. It has nothing to do with poverty or being from an oppressed socio-economic group. Osama is a wealthy man, his lieutenants are wealthy men, the 19 hijackers from 9/11 were from well to do backgrounds. They are the way they are not because of some social ill that can be addressed, but because their religion tells them that they are in a just cause. It a different world view.