Book excerpt: Three stories run through this book. One story comes from a collection of eyewitness accounts of combat. Intense, personal and often laced with dark humour, this story ties readers to the experience of combat. The main body tells the second story. This describes the hard science of tactical psychology, from its basic components to its most compelling effects. The third story is woven through the scientific themes and tied to the eyewitness accounts. It tells how the author was sucked into asecretive world of fighters and thinkers.