'The propagandist's purpose," wrote Aldous Huxley, "is to make one set of people forget that certain other sets of people are human." The British, who invented modern war propaganda and inspired Joseph Goebbels, were specialists in the field. At the height of the slaughter known as the First World War, the prime minister, David Lloyd George, confided to C. P. Scott, editor of the Manchester Guardian: "If people really knew [the truth], the war would be stopped tomorrow. But of course they don't know, and can't know."

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