Transitions from rivalry to alliance within bilateral relationships have received considerable attention from historians of U.S. foreign relations. Or, more accurately, some alliances have received considerable attention; it remains unusual for works on inter-American relations to be cast principally as examinations of alliance politics. There are at least two interrelated reasons. First, the vast majority of the literature on the foreign relations of Latin American states analyzes cases where significant asymmetries of power exist. To be sure, vast differentials in political, economic, and military power can be found within alliances. But the alliance framework is more often applied to cases of countries where the imbalance is not dramatic. Second, in the English language literature in particular, relations between Latin American countries have been understudied. The overwhelming majority of the scholarship analyzes the role of great powers such as the United States or Great Britain. Consequently, the factors that have led regional adversaries to become allies have received less attention. U.S.-Latin American relations or Anglo-Latin American relations could, of course, be studied through the prism of rivalries and alliances, but the frameworks of empire and other varieties of hegemony have been more commonly utilized.