Book excerpt: The old world of spying that emphasized the human factor--dead letter boxes, microfilm cameras, and an enemy reporting to the Moscow Center--is history. Or is it? In recent times, the spymaster's technique has changed with the enemy. He or she now frequently comes from a culture far removed from Western understanding and is part of a less well-organized group. The new enemy is constantly evolving and prepared to kill the innocent. In the face of this new threat, the spymasters of the world replaced human intelligence with an obsession that focuses on the technical methods of spying, ranging from the use of high-definition satellite photography to the global interception of communications. However, this obsession with technology has failed, most spectacularly, with the devastation of the 9/11 attacks. In this modern history of espionage, Stephen Grey takes us from the CIA's Cold War legends, to the agents who betrayed the IRA, through to the spooks inside Al-Qaeda and ISIS. Techniques and technologies have evolved, but the old motivations for betrayal--patriotism, greed, revenge, compromise--endure. Based on years of research and interviews with hundreds of secret sources, this is an up-to-date exposé that shows how spycraft's human factor is once again being used to combat the world's deadliest enemies.--Adapted from book jacket.