The belief that the United States had the right and duty to expand across the North American continent is called Manifest Destiny. This term was first coined in 1845 by newspaper editor John L. O’Sullivan, who argued that it was the United States' divine right and mission to overspread and possess the entire continent allotted by Providence for the development of liberty and democracy
. Manifest Destiny was rooted in the idea of American exceptionalism and the conviction that white Americans were divinely ordained to settle the continent from the Atlantic to the Pacific. It justified territorial expansion into regions like Oregon, Texas, New Mexico, and California, and was used as a rallying cry for policies and wars, such as the annexation of Texas and the Mexican-American War
. The concept was closely linked to the Monroe Doctrine and the idea of continentalism, which envisioned the United States eventually encompassing all of North America. While embraced by Democrats, it faced opposition from Whigs and abolitionists, who feared the expansion of slavery and questioned the moral and political implications of such expansion
. In summary, Manifest Destiny is the name given to the 19th-century belief that the United States was destined and had the right to expand across the North American continent
