As the subtitle indicates, The Hovering Giant is not a narrative history of United States relations with Latin America but an analysis of American reactions to revolutionary upheaval in the volatile political climate of the western hemisphere. A political scientist and founder of the Center for Latin American Studies at the University of Pittsburgh, Blasier has combined the methodological techniques of political science and the examples of history in a book that is informative, interpretive, and imaginative. It is also devoid of jargon, so often associated with treatises of this genre.

Blasier focuses on four revolutions: Mexico, Bolivia, Guatemala, and Cuba. Toward these four revolutions the United States reacted somewhat differently, but Washington policymakers confronted similar problems in each. In Mexico and Bolivia, for example, the United States displayed initial hostility to revolution but ultimately reconciled its policies to changes in those societies. In Guatemala and Cuba, by contrast, the United States eventually resorted to covert operations or paramilitary invasions to overthrow revolutionary governments.

Blasier contends, quite rightly, that no simple explanation of American reaction to Latin American revolution—such as determined measures to protect private business interests threatened with nationalization—will suffice. He describes stages of revolutionary change. In the first stage, when revolutionary movements got underway, the United States proved flexible. For example, it permitted Francisco Madero to organize against Porfirio Díaz on American soil. In the second stage, when revolutionary governments launched reformist programs, the United States has been antagonistic, especially if American private interests were threatened. In this stage, American officials were often insensitive or unappreciative of the obstacles confronted by revolutionary regimes striving to consolidate their power and initiate social change. In stage three, when revolutionary governments made sweeping political and economic alterations, the United States had the choice of accepting the new order, hoping to mitigate its impact, or of trying to overthrow the revolutionary government. Thus, the Mexican and Bolivian revolutions were ultimately accommodated because Washington believed these governments were flexible; in Cuba and Guatemala the revolutionaries in power were regarded as inflexible, and the United States decided to try to overthrow them.