David Dimbleby charts the changing relationship, not only at the top, but among the ordinary men and women who lived and fought together until Hitler had been defeated.

Harold Macmillan was determined to restore relations between Britain and America after the catastrophe of Suez. The launch of Russia's Sputnik was his opportunity: America needed nuclear bases in Europe, and Britain was prepared to offer them. But the atmosphere of goodwill was soured by Vietnam. American Secretary of State Dean Rusk put heavy pressure on Britain to send a token force in support. The British Government refused, to Rusk's dismay. 'When the Russians invade Sussex,' he said to one journalist, 'don't expect us to come and help you.'