Historian Robert Kagan has been writing about foreign affairs for most of his 64 years. The first book in his planned trilogy on American foreign policy was published in 2006 and focused on U.S. history before the founding up to the Spanish-American War. Mr. Kagan, a senior fellow at the Brookings Institution, has just completed the second book in the trilogy titled "The Ghost at the Feast: America and the Collapse of World Order, 1900-1941." He, in conclusion, writes: "Americans have complex attitudes toward power and morality. They have a sense of distinctiveness and remoteness in a tumultuous and highly contested political system."

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