“Manifest Destiny” is a phrase to describe the future of the United States that considerably impacted U.S. foreign policy in the 1840s and 1850s.
It was coined by John O’Sullivan in the editorial in Democratic Review in 1845 where he wrote about “”manifest destiny to overspread the continent” (Wikipedia, 2006). This phrase described the expansionist foreign policy doctrine that helped America reach its present boundaries.
The underlying idea of the doctrine was that the United States with its democratic system was in many ways superior to other nations. Therefore, it was morally obliged to expand in order to bring democracy and progress to new lands around. The virtue of the American nation, its superior abilities at development, and the mission to develop other neighboring parts of the continent formed the ideological basis for Manifest Destiny.
At the same time, this ideology served a number of practical implications that were relevant to the US foreign policy in the 1840s and 1850s. As such, it underlay the policy of continentalism that warranted the expansion on the American continent aiming to make America stretch “from sea to shining sea”. For example, it played a role in the Oregon dispute with Great Britain in which President Polk elected in 1844 at first agreed to divide the state at the 49th parallel, but then a campaign began, claiming all Oregon to belong to the United States.
In the relations with Mexico, the theme of Manifest Destiny was even more prominent. The decision of the Republic of Texas in 1836 to separate from Mexico and request entry to the United States was taken by many as evidence that the Untied States is indeed destined to “assemble” all neighboring territories. Although the Mexican-American War that started in 1846 was not successful in bringing all of Mexico under American rule, it nevertheless added California and New Mexico. For two decades, America remained concentrated on fulfilling its Manifest Destiny – annexing various territories and bringing them as states into the union.
Wikipedia. Manifest Destiny. http://en.wikipedia.org/wiki/Manifest_Destiny (accessed August 22, 2006)