Drawing on her investigative and literary talents, Julia Keller offers a riveting account of the invention of the world's first working machine gun. Through her portrait of its misunderstood creator, Richard Jordan Gatling-who naively hoped that the overwhelming effectiveness of a multiple-firing weapon would save lives by decreasing the size of armies and reducing the number of soldiers needed to fight-Keller draws profound parallels to the scientists who would unleash America's atomic arsenal half a century later. The Gatling gun, in its combination of ingenuity, idealism, and destructive power, perfectly exemplifies the paradox of America's rise in the nineteenth century to a world superpower.