Why do states miscalculate when making critical national security decisions? The structure of national security bureaucracies plays a pivotal role in determining the likelihood of miscalculation. This is because it directly shapes the quality of intelligence that reaches decision-makers, influencing their ability to assess threats, anticipate adversary responses, and make informed strategic choices. The U.S. escalation in Vietnam, where President Lyndon Johnson’s reliance on the insular “Tuesday Luncheon” group limited dissenting views, leading to an overestimation of American military leverage in an example of fragmented intelligence. Similarly, China’s miscalculations during the 1962 Sino-Indian War could also be attributed to the same problem that failed to provide Mao Zedong with a full picture of India’s military capacity and intent.

In Bureaucracies at War, Tyler Jost argues that these are examples of institutions that fundamentally determine the quality of information available to leaders. He identifies four broad categories of institutional design: inclusive, open institutions (integrated); inclusive, closed institutions (siloed); insular, closed institutions (fragmented); and insular, open institutions (dictatorial) (pp. 26–27). Integrated institutions “allow bureaucracies to access each other’s information” (p. 9), shaping strategic decisions. Siloed institutions, by contrast, restrict information flow despite maintaining a degree of inclusiveness, meaning that while multiple agencies exist, they do not always coordinate effectively. Fragmented institutions, such as those seen in Johnson’s Vietnam decision-making, insulate “the leader’s decision-making processes from the bureaucracy” (p. 9) and restrict inter-agency communication. Dictatorial institutions, while insular in leadership, allow open information channels within bureaucracies, meaning autocrats may receive a wide range of intelligence but retain discretion over its application.

Jost tests his framework through a series of historical case studies, comparing instances of strategic miscalculation across democratic and authoritarian regimes. The Vietnam War escalation under Johnson serves as a prime example of how fragmented institutions stifled dissent, leading to faulty assumptions about North Vietnam’s resolve and the effectiveness of U.S. military pressure. Likewise, the Sino-Indian War illustrates how Mao’s reliance on a narrow group of trusted advisors led to an underestimation of India’s willingness to fight, resulting in a war that Beijing did not anticipate would escalate so dramatically. In contrast, the book examines the Eisenhower administration’s handling of the 1958 Taiwan Strait Crisis, showing how an integrated institutional structure facilitated a more comprehensive assessment of risks and adversary intentions, allowing the U.S. to avoid unnecessary escalation.

Jost’s argument challenges dominant explanations of strategic miscalculation, which often attribute mistakes to individual leader psychology, ideological rigidity, or structural constraints in the international system. Instead, he emphasizes that the flow of information within national security institutions is often a more decisive factor than individual competence or geopolitical pressures. By foregrounding bureaucratic design as a central explanatory variable, Bureaucracies at War presents a novel institutionalist account of decision-making under uncertainty.

Jost’s book makes an important contribution to several areas of political science, particularly the study of bureaucratic politics, international security, and decision-making under uncertainty. While existing literature in international relations often focuses on structural determinants of state behavior—such as power transitions or alliance politics—Bureaucracies at War shifts the focus inward, examining how internal institutional structures shape states’ external behavior. In doing so, Jost builds on and extends earlier bureaucratic politics models, such as Graham Allison’s Essence of Decision, but with a sharper emphasis on how institutions mediate the distribution and use of intelligence.

Moreover, the book offers a significant intervention in debates over the role of expertise in policymaking. Jost demonstrates that even highly competent bureaucracies can produce flawed strategic assessments if they operate within institutions that stifle inter-agency collaboration. This insight is particularly relevant to contemporary policy discussions, where concerns over intelligence failures—whether in the context of the Iraq War, Russian intervention in Ukraine, or evolving U.S.–China relations—underscore the importance of institutional design in shaping national security decision-making.

The book also refines existing scholarship on authoritarian decision-making. Conventional wisdom holds that authoritarian regimes struggle with information asymmetries because subordinates fear providing bad news to autocrats. Jost’s analysis, however, suggests that institutional structure plays a crucial mediating role: while some authoritarian systems suffer from extreme information compartmentalization, others develop workarounds—such as informal advisory networks or intelligence-sharing mechanisms—that allow for more effective decision-making. His comparative analysis of China, India, and Pakistan underscores how variation in institutional design affects authoritarian regimes in different ways, rather than assuming a one-size-fits-all model of autocratic decision-making.

While Bureaucracies at War offers a compelling framework for understanding miscalculation, certain aspects of its argument are thought-provoking. One potential question is about the ability to classify an action as miscalculation in real time versus retrospectively. Jost’s framework largely assumes that certain decisions—such as the U.S. escalation in Vietnam or China’s approach to the Sino-Indian War—represent clear strategic blunders. However, strategic outcomes are often ambiguous and subject to reinterpretation over time. For instance, the recent Russian invasion of Ukraine was perceived as a miscalculation at the beginning given the vast economic sanctions imposed on Russia. However, shifts in geopolitical conditions—such as changing Western domestic politics or prolonged economic disruptions—could potentially lead to analysts regarding the Russian invasion as successful action. This raises the broader epistemological challenge of whether miscalculation can be meaningfully identified ex ante or if it is inevitably a post hoc assessment shaped by subsequent events.

The book’s rich conceptual framework offers valuable insights into the role of institutions in shaping national security decision-making. At the same time, its broad typology invites further reflection on how different forms of institutional integration and compartmentalization influence outcomes. While the distinction between integrated and siloed institutions is analytically useful, there may be additional nuances worth exploring. Not all forms of integration necessarily lead to optimal decision-making, just as not all forms of bureaucratic compartmentalization result in miscalculation. In some cases, extensive interagency deliberation can slow decision-making, while more centralized structures may enhance strategic clarity. Building on Jost’s framework, future research might consider distinguishing between different types of institutional integration—such as hierarchical integration, where information flows through clear command structures, versus horizontal integration, where multiple agencies contribute equally to shaping policy.

Additionally, the book’s discussion of competence, motivation, and access to information as key factors in institutional effectiveness presents an important and thought-provoking approach. While these variables are deeply interconnected, there may be instances where they operate in distinct ways. For example, a highly competent bureaucracy may still face constraints in disseminating intelligence due to political leadership dynamics, while a motivated bureaucracy does not necessarily translate into effective decision-making if mechanisms for vetting information are weak. Further unpacking how these factors interact could enrich our understanding of how institutional structures influence strategic assessments.

Bureaucracies at War offers valuable insights for both scholars and policymakers. The book’s findings have direct implications for contemporary security challenges, particularly in cases where institutional weaknesses contribute to miscalculation. For instance, understanding how institutional design affects crisis management could be highly relevant in analyzing U.S.–China relations, where intelligence-sharing mechanisms and inter-agency coordination will be crucial in preventing unintended escalation. Similarly, Jost’s framework could be applied to emerging security threats, such as cyber warfare and artificial intelligence, where bureaucratic adaptation to new forms of intelligence processing will shape strategic outcomes. The book will be of great interest to scholars of international relations, security studies, and bureaucratic politics, as well as policymakers seeking to understand how institutional structures influence the quality of decision-making. At a time when global security challenges are increasingly complex, Jost’s insights into the institutional origins of miscalculation are both timely and essential.