How did manifest destiny relate to the conduct of American diplomacy in the 1840s?

Answer 1

Manifest Destiny was the term used to describe the idea in the United States, beginning in the 1840s, that the US was destined to expand from ocean to ocean and all of North America from north to south. It developed, in part, from a great surge of nationalism (patriotism) following the War of 1812, as the nation expanded west. Because of our economic and political superiority, and due to the rapid growth of our population, and because it was God's will, our superior civilization should take over the others on the continent. In 1845, John L. O'Sullivan wrote an article about the annexation of Texas and first used the term, manifest destiny. The idea was revived toward the end of the 1800's during the Spanish-American War, and also led to the the US becoming an imperialistic nation at the turn of the century.

Answer 2

The manifest destiny theory was an idea that said that America was destined to rule the continent from coast to coast. This encouraged the government to expand west leading to conflicts with native Americans. This also was a big reason for the civil war as there was a debate whether slavery was to be allowed in the new states and territories out west.