Scholars often assume that as a global superpower, the United States has had great influence and impact on political regime developments in the world. This article critically examines these claims, focusing on Latin America; by investigating the region most directly dominated by the US, it employs a most-likely-case design. The experiences of countries such as Brazil, Chile, Haiti, Nicaragua, and Venezuela show that US influence has been fairly limited for many years and has diminished over time. The Northern superpower has been less involved and has had less impact on regime developments than often postulated, as the analysis of the coups in Brazil in 1964 and Chile in 1973 demonstrates. Moreover, nations to which the US has maintained close, comprehensive linkages, such as Venezuela, have slid into “competitive authoritarianism” while a country such as Haiti, over which the US holds great leverage, has failed to establish a functioning democracy. Thus, even in its direct sphere of interest, the most powerful nation in the contemporary world seems to be limited in its capacity to promote or prevent political regime change.