Manifest Destiny was a concept developed by Polk; it was a plan for the Anglo-Saxon Americans to expand westward toward the Pacific Ocean. In 1845, John L. O'Sullivan described the annexation of Texas by extension and the right to occupy the remainder of the territory as a right of the American people. Manifest Destiny was a term used to justify the annexation of Oregon, New Mexico, and California. Manifest Destiny would become responsible for the annexation of Texas, but also responsible for the war with Mexico (1846-1848). A few Americans objected, mostly abolitionists, but nothing was done about it. The end result would be freedom and economic freedom. The 3 major keys to Manifest Destiny were the virtue of the American people and their institutions, the mission to spread these institutions, and the God-given destiny of accomplishing this work. These concepts were satisfied by the Oregon Treaty of 1846. Initially, Polk wanted lands up to the 49th parallel, but he knew that Britain would not be so quick to negotiate. So, he devised a plot so he could achieve it with little to no conflict. Polk approach...