The first half of the book explores the ideas upon which groups such as Al Qaeda are built, including the concepts of Jihad, al-Wala wal-Bara, Takfir and Tawhid. Jarret Brachman exposes a genre of Jihadist strategic scholarship that has been virtually ignored in the West and helps to situate it within the broader Salafist religious movement. The second half explores the thinking and activities of Al Qaeda’s propaganda machine, explaining its intricacies and idiosyncrasies. It includes case studies on the rise and fall of global Jihadist terrorism in Saudi Arabia post-9/11, and highlights the explosive results of bringing theory to bear on practice in the United Kingdom over the past twenty years. The book concludes by providing innovative strategies for combating the global Jihadist ideology.