Dividing the subject into armament epochs - Ages of Valour, Chivalry, Gunpowder, Steam, Oil, and Atomic Energy - Fuller examines the most influential military innovations of each period as well as the key leaders (including Alexander, Caesar, Gustavus Adolphus, and Napoleon) who skillfully employed these weapons. Although the author acknowledges that war cannot be eliminated entirely, he urges man to impose restrictions on warfare, as had been done in past centuries, before society descends into a second Dark Age. Completed immediately after the bombings of Hiroshima and Nagasaki - chilling examples of mass destruction caused by armaments - this impassioned work remains relevant a half-century later.