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Manifest Destiny is a catch phrase describing the belief, characteristic of the United States of America of the 19th century, of the necessity and justification of expansionism, with a hint that the United States of America should stretch from the Atlantic to the Pacific Oceans. During the Mexican-American War and later, the term was used to justify the annexation of the western territories of Mexico (Arizona, Texas, California, etc.). On the eve of the Spanish-American War, the term was revived by the Republicans to provide a theoretical basis for US overseas expansion to the Caribbean.