The Great and Holy War: How World War I Became a Religious Crusade,by Philip Jenkins

The roots of today’s sectarian-fueled conflicts lie in the First World War. By igniting “a global religious revolution,” the “Great War” redrew the world’s religious map both figuratively and literally. Modern Islam, characterized as “assertive, self-confident, and aggressively sectarian,” is a direct result, but so too are the spread of charismatic Christianity in Africa, an invigorated Zionism that led to the eventual creation of the modern state of Israel, and even the “efflorescence of esoteric and mysti- cal ideas that we often summarize as New Age.