I would recommend that you look into Maajid Nawaz’s memoir Radical. As a former Islamist, he describes how he became radicalized in his youth and how he became disillusioned when jailed in Egypt in the early 2000s. He’s now a passionate advocate of democratic culture and has founded a counter-extremist think tank, the Quilliam Foundation. He has a wealth of firsthand insight into radicalization and the best ways to defeat their ideology.