The typical military history presents a chronicle of battles and wars and the commanders and troops who fought them. This book takes a different approach. It presents battles and wars and people aplenty, but they are not its ultimate subjects. This book is about the turning points that not only make military history dynamic but crucial to the story of humanity and civilization. This book is about the decisions, acts, innovations, errors, ideas, successes, and failures that shaped the evolution of military art and science-strategy, tactics, and technology -- and, in doing so, shaped the course of world history.