"Animal Farm" and "1984" are required reading for students of both British and American culture, but George Orwell was more an essayist than he was a novelist. Two volumes of his essays, Facing Unpleasant Facts and All Art is Propaganda, have just been published, and they have much of the same, punchy relevance today that they did 60 or 70 years ago. George Packer, author of The Assassins Gate: America in Iraq and a staff writer for the New Yorker magazine, edited the two-volume set.