John Boyd may be the most remarkable unsung hero in all of American military history. Some remember him as the greatest U.S. fighter pilot ever — the man who, in simulated air-to-air combat, defeated every challenger in less than forty seconds. Some recall him as the father of our country’s most legendary fighter aircraft — the F-15 and F-16. Still others think of Boyd as the most influential military theorist since Sun Tzu. They know only half the story.