http://www.nytimes.com/2015/03/22/world/middleeast/from-minn...
Modern liberalism offers no solution to the problem of evil. It assumes that as long as your basic needs are met, and you're mentally sane, that you will behave as a rational, non-violent person. It sees humans as essentially materialist, subject to the same universal desires, which can all be met in similar ways, and which are never distorted to any great degree. So it is stumped by the sort of despair that such jihadists harbor in their hearts, for according to its philosophical principles, such a thing should not be possible.