Contrary to the beliefs of New Left historians seeking to revive the once discredited theory that American territorial expansion was driven by a motivation to expand the institution of slavery, a position that I have dubbed the Neo-Abolitionist view, rather that Manifest Destiny developed as an early national security strategy and primitive strategic doctrine, what might be termed in today’s vernacular as a kind of preemptive threat displacement theory. That is, early on in the history of the Republic, many American statesmen believed that the most effective means of preventing a “balance of power” geopolitical system from being established in North America was to reduce the number of independent sovereignties on the frontiers of the United States through the annexation and incorporation of such territories into the Union. Also, how Americans dealt with apprehensions of encirclement and the “problem of neighborhood” in connection with the “balance of power” concept as well as how these concerns related to ongoing fears of domestic insurrections, Indian uprisings, and Slave rebellions is the focus of this dissertation.