The timely message that peace does not preserve itself opens this study of the origins of mankind's greatest and most destructive wars. The author, a distinguished American historian, considers four mammoth wars, and one near-disaster, the Cuban missile crisis. He reveals the common threads which connect the ancient confrontations between Athens and Sparta, and between Rome and Carthage, with the two calamitous world wars of our own century - against the German military machines of Kaiser Wilhelm and Adolf Hitler. What were the real failures which led to world war in 1914? In the years leading up to World War II, were the appeasers of the 1930s solely to blame for Hitler's rise, or were the most important errors made in the peaceful 1920s. In the Cuban missile crisis, did President Kennedy really make Khruschev blink? Donald Kagan's answers to these questions challenge most traditional interpretations.