Violence, a major means of elite attack and defense, takes many forms. The number of men who have been permanently included in the armed forces of the world gives some indication of the place of violence in politics.
In the early Roman Empire the standing army had about 300,000 men, or three in every thousand persons. Undoubtedly this was the largest standing army of ancient times. In the thirteenth century, Europe is estimated to have had the same proportion of its population under arms, though dispersed in a swarm of tiny principalities. By the early seventeenth century, Europe regained a population equal to that of the Roman Empire, and expanded both in numbers and in proportion in the army. During the Napoleonic period France sometimes had ten in every thousand persons under arms, and before the end of the nineteenth century all peacetime establishments of the great powers had climbed to this Napoleonic peak. During the World War no less than one hundred in every thousand of population were in arms. By 1934 the standing armies of Europe were twice the relative size of the Roman armies under Augustus.
The length of wars has declined, however, and so has the proportion of war years to peace years, if expeditions against peoples of inferior technique are excluded from the count. In the seventeenth century the great European states were at war about 75 per cent of the time. In the eighteenth century the per cent is 50; in the nineteenth cen-