David Sylvan and Stephen Majeski have written an ambitious and provocative book that makes an important contribution to the study of U.S. foreign policy. The authors set out to document and explain continuity in U.S. foreign policy since the Spanish American War (1898). They argue that over the past century, the United States has steadily expanded and supported its “clients” and opposed its “enemies.”

Sylvan and Majeski define (p. 29) a client as “a state for which the maintenance of its regime … is (1) considered by the U.S. government as a legitimate matter of concern which (2) is worth considerable political and, if need be, economic and military efforts, should the regime be seen as endangered.” They add that the dominant political forces in the client must see the relationship of the United States with their country as normal and legitimate. They write (p. 45) that an “enemy is a nonclient whose regime is seen as choosing systematically to differ with the U.S. on key issues of foreign and domestic economic and political policy.” According to the authors, there were roughly 80 U.S. clients and six enemies as of August 2006.

The authors' analysis draws on cybernetic theory, which emerged to make sense of organizations that become so engaged in designing and maintaining systems that they lose sight of the core goals that ostensibly motivate them. They argue that since 1898, the U.S. government has developed policy instruments (capabilities embedded in organizations) from which it chooses to preserve clients and oppose enemies. The authors posit that policy instruments have immediate goals or “missions” (e.g., improving the effectiveness of a client's military), and feedback serves to correct errors in whether the instrument achieves the mission. They argue that U.S. government officials possess an ideology wherein it is normal to acquire and maintain clients while opposing enemies. As a result, the U.S. government rarely assesses whether having a particular country as a client or enemy meets its core goals (they suggest that the United States gains very little from many clients). Sylvan and Majeski further argue that the country's network of clients constitutes an empire in that Washington continually constrains its clients' fundamental options.

Following the development of the theoretical argument, the heart of the book consists of a dazzling array of data on routine client maintenance, as well as case studies of intervention in support of clients and intervention against enemies (with additional cases available on the book's Website). The authors develop a sophisticated typology of each kind of action and carefully document U.S. action in practice. They demonstrate that the United States chooses a particular way of intervening as a result of the nature of the problem it faces and the means it has available (i.e., it is not primarily motivated by the core goals it seeks to achieve).

U.S. Foreign Policy in Perspective will be of interest to scholars specializing in alliance politics, intervention and statecraft, and bureaucratic politics explanations of foreign policy. The book is also of great policy relevance as the Obama administration deliberates on how best to maintain clients in Southwest Asia and elsewhere.

The book's most noteworthy attribute is its ability to explain the persistence of American clients and allies long past the initial conditions that lead the United States to adopt them. In 1993, Kenneth N. Waltz predicted (“The Emerging Structure of International Politics,” International Security 18 [Autumn 1993]: 76) that because of the collapse of the USSR, “NATO's days are not numbered, but its years are.” Almost two decades later, NATO shows no signs of imminent collapse. More recently, scholars and analysts have begun to make a strong case that the United States gets far too little and pays far too much for its allies (see Rajan Menon, The End of Alliances, 2007; Christopher A. Preble, The Power Problem, 2009). Yet, the United States continues to maintain a broad array of allies and to intervene on their behalf. Sylvan and Majesky provide a novel and compelling explanation of this behavior.

Of course, the book has its weaknesses. First, the authors' definition of “client” raises some concerns. It borders on tautology to say that a U.S. client is a country for which the United States sees regime maintenance as a legitimate matter of concern and for which it is willing to incur costs if one further uses the fact that the state is a client to explain U.S. maintenance activities. Moreover, there is tremendous variance in America's relationship with states that Sylvan and Majeski categorize as clients. Clients' relative power and value to the United States vary significantly, and it is folly to ignore that these factors fundamentally condition the relationship. Is the high-level military and intelligence cooperation the United States engages in with Britain equivalent to the surveillance and aid activities it engages in with Grenada?

Second, the authors might have referenced more of the relevant literature. They make almost no reference to the alliance politics literature, recent work on bureaucratic politics and organizational culture, or comparative studies of U.S. intervention in the post–Cold War era. The book's theoretical argument might have benefited from the discussion of complementary works. For example, Jae-Jung Suh's work on the U.S.–South Korea alliance (Power, Interest, and Identity in Military Alliances, 2007) looks at how elements of the bureaucracy and other societal forces contribute to alliance durability.

Third, while the authors make a convincing case for inertia in client maintenance, they go too far in denying the primary role that threat played in American client acquisition. They state (p. 55) that “when the U.S. does conclude formal alliances, it has little to do with a sense that these pacts are a way of fending off danger.” Specifically, they claim (p. 56) that Soviet threat cannot explain the North Atlantic Treaty because “[u]p until the Korean War, U.S. leaders simply were not worried about military threats from the U.S.S.R.” The authors provide too little support for a statement so at odds with the consensus view that President Harry Truman and Secretary of State Dean Acheson were convinced that the Soviets posed a comprehensive threat by 1947 and that this view played a critical role in the U.S. agreement to defend Western Europe (e.g., see George Herring, From Colony to Superpower, 2009).

Finally, the book would have been stronger had the authors restricted themselves to documenting and explaining client maintenance and intervention. Their treatment of enemies is provocative, but it raises more questions than anyone could effectively answer in a chapter. The book would have been improved by a handful of more detailed, process-tracing studies of some of the client cases, including tough cases for the book's argument like those where the United States chose to let clients go (e.g., South Vietnam or Iran). Detailed case studies might also have allowed the authors to put greater light on the role of feedback in the development of policy instruments as emphasized by cybernetic theory.

These criticisms should not overshadow the significant contribution the book makes in documenting and explaining U.S. client maintenance. It concludes with responses to works suggesting that the continuity that Sylvan and Majeski describe is coming to an end. The authors convincingly rebut those who expect the U.S. relationship with its clients to change. They make a strong case that clientelism will persist and, as such, U.S. Foreign Policy in Perspective will continue to help us understand this important facet of American foreign policy.