Manifest Destiny is the American belief that its borders should one day be destined to spread from one coast to the other. Theoretically, this could have included most of North America, but eventually the idea of including Mexico and Canada was discouraged. The term was first specifically coined by John L. O'Sullivan in 1845, and it was popularly advocated by Democrats, particularly the James Polk administration. By the beginning of the Civil War, however, the idea of manifest destiny was no longer viable. Advocates believed that it was a "divine right" to increase American borders, in part because of the idea that Americans (and/or speakers of the English language) were superior to others.
The Manifest Destiny is an axiom, or maxim, that was first mentioned in the mid 1800's in an editorial published by the United States Magazine and Democratic Review.
Although the editorial was anonymous, it was later on credited to the magazine editor, John O' Sullivan. The writing was motivated by the annexation of Texas, a massive territory, into the United States. As a result of this addition, the author is quoted with the following message:
"our manifest destiny to overspread the continent allotted by Providence for the free development of our multiplying millions."
Eventually, this message caught on with the public and was used in many more instances during U.S. history when more land was acquired and more states joined the Union. Both, the Democratic party and Conservative groups, have, at one time or another, adopted the idea of a manifest destiny to spread their patriotic messages.
Conclusively, the manifest destiny is the patriotic paradigm that the United States is a great nation which is meant to become bigger, and greater with the "blessing" of destiny.
the conquering of all lands.