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thought that the civilizations in the u.s. should stretch from sea to shining sea

In the words of Daria: << Manifest Destiny was a popular slogan in the 1840s. It was used by people who claimed it was God's will for the U.S. to expand all the way to the Pacific Ocean. These people did not include many Mexicans. >>

It wasn't just that "civilization" should cover the continent, but included the idea that it could be done by force when necessary in dealing with the natives.