We are living through one of the most important processes of recent history, the liquidation of an empire that has lasted in various forms for about two hundred and fifty years. It is a tribute to the people who gave it life, to their courage, political flexibility, and foresight, that, despite the changes and the retreats, they are still reckoned a power in world affairs. History has its lessons. In 1785 Britain had lost her most important overseas possessions, the American colonies, and the courts of Europe rejoiced at the discomfiture of the island people and their armies and navies. A third of a century later the British had organized the coalition that ultimately defeated Napoleon, the supreme military genius of his time, and were carving out a new empire in India, Australia, and Africa. We need not drop back so far in history. When, shortly before the Second World War, I went to England, it was fashionable and very profitable to write about the decay of Britain. Some very good books were written on the subject, and they were being seriously discussed when this island people, alone, in a tremendous renaissance of national energy, won the Battle of Britain and saved the Western world from the danger of German domination. As generations of Spaniards, French, and Germans have learned, it is unwise to count the British out. Yet an observer from Mars limiting his observations to the home islands would find reason to do so today. For the Britain of today resembles very little the Britain that, despite the long and, by the standards of that day, costly war in South Africa, greeted the twentieth century proudly confident. Britain's old position as "the workshop of the world" has vanished. There are now two other Britains--two nations, that is, which depend largely on the production and export of manufactured goods to live. Both these nations, Germany and Japan, are the defeated enemies of World War II, and both of them were bidding for and getting a share of Britain's overseas trade before that war and, indeed, before World War I. The decline in Britain's economic strength did not begin in 1939. The second world conflict, beginning only twenty-one years after the close of the first, accelerated the decline. Into World War II Britain poured both blood and treasure, just as she had in the earlier conflict. But 1914-18 had left her less of both. British casualties in World War II were smaller than in the first conflict, but the damage done to Britain's position in the world was much greater. The differences between the Britain of 1939 and the Britain of 1945 affected much more than the international position of the country. A society had been grabbed, shaken, and nearly throttled by the giant hand of war. After that bright Sunday morning in September when the sirens sounded for the first time in earnest, things were never the same again.