American expansion has always been associated with an emphasized sense of morality and grounded in ideals of exceptionalism and a sense of mission. Craftily coined ideologies, the most important of which is the well-known manifest destiny, and a human rights-based rhetoric that constituted a fixture across different administrations, painted expansion as the product of an altruistic desire to spread democracy and further human rights into new realms. Associating these ideals, namely expansion and morality, led to the emergence of the well-known frontier thesis which was seen by Frederick Jackson Turner as “the core defining quality of the United States”. It also produced expectations of a foreign policy that would champion the oppressed and make of morality and human rights its major guiding principles. The scrutiny of American post-Second World War policy in various countries of the third world, however, makes it clear that expansion in these parts of the globe clearly failed this frontier thesis as a welldefined set of materialistic interests, and not morality, has dictated foreign policy decisions towards the governments of these nations. These issues are scrutinized in depth in this research.