I found this article about ex-jihadis interesting, because these men who had allowed their minds to be taken over by extremism, describe the moments when a small sliver of light got in. Just enough to get them doubting, questioning, what they had seen as truth. A simple act of humanity--a gift from an old man---helped one man see fellow humans where before he had seen enemies. Another man realized that democractic principles were not a joke after seeing Amnesty International in action. These men started harboring doubts about the perfect society their leaders had promised, and questioned the morality of what they were doing.
One man has gone so far as to allow himself to listen to music for the first time in his life, something that was forbidden before. But he is not free to speak openly about it. He confesses to the journalist that he listens to music on his car radio and giggles about it, saying, "you'll get me killed." He likes "everything in the charts," and gives the journalist the names of some of the bands, but later calls and asks that the names not be printed, saying, "That would be a step too far."
"Question with boldness even the existence of a God; because, if there be one, he must more approve of the homage of reason, than that of blind-folded fear." ---Thomas Jefferson