Coercion
The Power to Hurt in International Politics
Edited by Kelly M. Greenhill
Peter Krause
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CONTENTS
Acknowledgments vii
List of Contributors ix
Introduction xi
Kelly M. Greenhill and Peter Krause
PART I | Coercion: A Primer
CHAPTER 1 Coercion: An Analytical Overview 3
Robert J. Art and Kelly M. Greenhill
CHAPTER 2 Intelligence and Coercion: A Neglected Connection 33
Austin Long
PART II | Coercion in an Asymmetric World
CHAPTER 3 A Bargaining Theory of Coercion 55
Todd S. Sechser
CHAPTER 4 Air Power, Sanctions, Coercion, and Containment: When Foreign Policy Objectives Collide 77
Phil M. Haun
CHAPTER 5 Step Aside or Face the Consequences: Explaining the Success and Failure of Compellent Threats to Remove Foreign Leaders 93
Alexander B. Downes
PART III | Coercion and Nonstate Actors
CHAPTER 6 Underestimating Weak States and State Sponsors: The Case for Base State Coercion 117
Keren E. Fraiman
CHAPTER 7 Coercion by Movement: How Power Drove the Success of the Eritrean Insurgency, 1960–1993 138
Peter Krause
CHAPTER 8 Is Technology the Answer? The Limits of Combat Drones in Countering Insurgents 160
James Igoe Walsh
PART IV | Domains and Instruments Other than Force
CHAPTER 9 Coercion through Cyberspace: The Stability-Instability Paradox Revisited 179
Jon R. Lindsay and Erik Gartzke
CHAPTER 10 Migration as a Coercive Weapon: New Evidence from the Middle East 204
Kelly M. Greenhill
CHAPTER 11 The Strategy of Coercive Isolation 228
Timothy W. Crawford
CHAPTER 12 Economic Sanctions in Theory and Practice: How Smart Are They? 251
Daniel W. Drezner
CHAPTER 13 Prices or Power Politics? When and Why States Coercively Compete over Resources 271
Jonathan N. Markowitz
PART V | Nuclear Coercion
CHAPTER 14 Deliberate Escalation: Nuclear Strategies to Deter or to Stop Conventional Attacks 291
Jasen J. Castillo
CHAPTER 15 Threatening Proliferation: The Goldilocks Principle of Bargaining with Nuclear Latency 312
Tristan Volpe
Conclusion 331
Kelly M. Greenhill and Peter Krause Index 349
ACKNOWLEDGMENTS
This book grew from a shared realization that the foundational scholarship on coercion that we regularly read, taught, and utilized was no longer adequate to explain much of the behavior we observed in the world around us. From forced migration in the Middle East and North Africa to cyber threats from Russia (and targeted sanctions on Russia), and from drone strikes in South Asia to terrorist attacks across the globe, understanding contemporary coercive dynamics clearly requires an expansion of our analytical toolbox to include new concepts, theories, and analyses. We are enormously gratified to be joined in this endeavor by a diverse array of experts who offer innovative and penetrating contributions on a diverse array of coercive tools, actors, and environments. Our editor, David McBride of Oxford University Press, offered enthusiastic encouragement from the outset, and his and the external reviewers’ sharp insights helped shape the final product into a more cohesive and powerful book.
We thank the faculty and researchers of the MIT Security Studies Program, where we first rigorously studied coercion and learned to appreciate its myriad shades and manifestations. Kelly M. Greenhill further thanks Tufts University and the International Security Program (ISP) at Harvard University’s Belfer Center for their intellectual and financial support of her research and, in the case of ISP, for its support of the Conflict, Security and Public Policy Working Group, out of which a number of contributions to this volume grew. She also thanks her besheryt for providing inimitable daily reminders that effective persuasion and influence also come in noncoercive packages. Peter Krause would like to thank all members of his research team, the Project on National Movements and Political Violence, especially Eleanor Hildebrandt. He also thanks his colleagues and administrators at Boston College, who provided academic and financial support for this volume. Finally, he thanks his parents and sisters who, in addition to a great deal of love, gave him his very first lessons in the causes, strategies, and effectiveness of coercion.
CONTRIBUTORS
Robert J. Art is Christian A. Herter Professor of International Relations at Brandeis University.
Jasen J. Castillo is Associate Professor in the Bush School of Government and Public Service at Texas A&M University.
Timothy W. Crawford is Associate Professor of Political Science at Boston College.
Alexander B. Downes is Associate Professor of Political Science and International Affairs at the George Washington University.
Daniel W. Drezner is Professor of International Politics at Tufts University’s Fletcher School of Law and Diplomacy.
Keren E. Fraiman is a member of the faculty at the Spertus Institute.
Erik Gartzke is Professor of Political Science and Director of the Center for Peace and Security Studies at the University of California, San Diego.
Kelly M. Greenhill is Associate Professor and Director of the International Relations Program at Tufts University and Research Fellow at Harvard University’s Kennedy School of Government.
Phil M. Haun is Professor and Dean of Academics at the US Naval War College.
Peter Krause is Assistant Professor of Political Science at Boston College and Research Affiliate at the MIT Security Studies Program.
Jon R. Lindsay is Assistant Professor of Digital Media and Global Affairs at the University of Toronto’s Munk School of Global Affairs.
Austin Long is Senior Political Scientist at the RAND Corporation.
Jonathan N. Markowitz is Assistant Professor in the School of International Relations at the University of Southern California.
Todd S. Sechser is Associate Professor of Politics at the University of Virginia.
Tristan Volpe is Assistant Professor of Defense Analysis at the Naval Postgraduate School and Nonresident Fellow at the Carnegie Endowment for International Peace.
James Igoe Walsh is Professor of Political Science at the University of North Carolina.
INTRODUCTION
Kelly M. Greenhill and Peter Krause
From the rising significance of nonstate actors to the increasing influence of regional powers, the nature and conduct of international politics has arguably changed dramatically since the height of the Cold War. Yet much of the existing literature on deterrence and compellence continues to draw, whether implicitly or explicitly, upon assumptions and precepts formulated in a state-centric, bipolar world. Although contemporary coercion frequently features multiple coercers targeting state and nonstate adversaries with nonmilitary instruments of persuasion, most literature on coercion focuses primarily on cases wherein a single state is trying to coerce another single state via traditional military means.
This volume moves beyond these traditional premises and examines the critical issue of coercion in the twenty-first century, capturing fresh theoretical and policy-relevant developments and drawing upon data and cases from across time and around the globe. The contributions examine intrastate, interstate, and transnational deterrence and compellence, as well as both military and nonmilitary instruments of persuasion. Specifically, chapters focus on tools (e.g., terrorism, sanctions, drones, cyber warfare, intelligence, and forced migration), actors (e.g., insurgents, social movements, and nongovernmental organizations), and mechanisms (e.g., triadic coercion, diplomatic and economic isolation, foreign-imposed regime change, coercion of nuclear proliferators, and two-level games) that have become more prominent in recent years but have yet to be extensively or systematically addressed in either academic or policy literature.
At the same time, there is also significant continuity in how states wield power and exercise influence. Strategic and crisis deterrence, threats backed with military force, and exercises of state-on-state coercive diplomacy are enduring features of international politics. Consequently, there remains a great deal of relevant wisdom in existing scholarship on coercion. Therefore, this volume also features
chapters that proffer novel and innovative theoretical approaches to historical exercises in coercion and highlight the contemporary implications of historical cases. An introductory chapter offers an overview of the state of our knowledge about the theory and practice of coercion and analyzes the extent to which previous theories and arguments apply to current and future coercion challenges.
The chapters in this volume employ a variety of analytical tools and methods, including rational choice modeling, deductive theory building and extension, historical case study analysis, and large- and medium-N statistical analysis to shed new light on an old issue. The authors are equally diverse in their paradigmatic viewpoints, and several of the contributions wholly defy ready categorization in this regard. Power and its distribution, institutions, norms, ideas, and information all play analytically important roles, and several of the chapters combine these well-known variables in novel ways. In a similar vein, some commonly recognized theoretical concepts are deployed in as yet underappreciated yet analytically quite profitable ways. In sum, while no single volume of several hundred pages can be truly comprehensive, this book offers readers a hearty and edifying brew of old and new, of continuity and change, and of the theory and practice of coercion.
The volume is organized into five sections that speak to our focus on increasingly relevant actors, tools, and mechanisms in the study of coercion. Taken as a whole, the contributors approach the topic of coercion with three key questions in mind: What have we long known and still know to be true about coercion? What did we once think we knew, but now know needs to be revised or reconsidered? What did we simply not think about before now? The next section offers a brief description of each of the chapters within the five sections and their initial answers, grouped by relevant themes. The final section offers some ideas for instructors and others seeking to use this book to get smart about the power to hurt in today’s world.
A Preview of the Chapters in This Volume
Coercion: A Primer
The volume opens with an introductory essay by Robert J. Art and Kelly M. Greenhill that lays the groundwork for the chapters that follow by offering an analytical overview of the state of the art in the study of coercion. Their chapter is loosely organized around the three key questions that motivate this volume. Art and Greenhill systematically interrogate the premises that undergird our assumptions about coercion and explore issues of continuity, change, and innovation in our understanding of coercion in the twenty-first century. In addition to identifying foundational insights from the traditional (state-tostate, Cold War–focused) coercion literature, the authors also highlight more recent, post–Cold War contributions as well as particular questions and heretofore underexplored topics examined by the contributors to this volume.
In chapter 2, Austin Long extends Art and Greenhill’s discussion of coercion by analyzing its understudied yet integral connections with intelligence. Drawing upon evidence from Iraq to illustrate his key propositions, Long identifies three central ways in which intelligence and coercion are inextricably linked. First, intelligence provides a coercer with an understanding of a target’s values, resolve, and capabilities, and thus the capacity to evaluate whether coercion is feasible. Second, intelligence effectively directs the tools of coercion—whether military force or economic sanctions—at specific elements of a target’s political, economic, or military assets. Third, intelligence provides a discrete mechanism of influence—covert action—that lies between the overt use of military force and other nonviolent mechanisms of coercion. In addition to highlighting the underappreciated role of intelligence, Long sets the stage for subsequent contributions that focus on the importance of information in effecting successful coercion.
Coercion in an Asymmetric World
Coercion is often not a confrontation among equals. Instead, stronger states regularly employ threats and the limited use of force against weaker ones. As the chapters in this section demonstrate, however, superior strength is insufficient to guarantee coercive success and, in some cases, can even be an obstacle to success. The authors in this section reveal that the coercer’s selection of target and specific policy demands—often made amid significant uncertainty— drive the initiation, dynamics, and outcomes of coercion.
In chapter 3, Todd S. Sechser employs rational choice theory to delve into the dynamic, iterative processes that characterize the bargaining game that is coercive diplomacy. Sechser develops a model of crisis bargaining to evaluate the strategic choices faced by coercers. He explores how coercers weigh their desire for gains against the risk of war that inevitably rises when they make threats and demand concessions of targets, as well as how power and (often imperfect) information play into these calculations. Sechser’s analysis generates two counterintuitive hypotheses that challenge conventional wisdom about coercion. First, greater military power emboldens coercers to make riskier demands, increasing the likelihood of coercion failure. Second, coercers are motivated to attenuate their demands when target resolve is high, thereby making coercion success against resolved adversaries more likely. Both insights underscore the importance of the magnitude of coercers’ demands in analyses of coercive bargaining.
Focusing on the employment of coercion using both military and nonmilitary instruments of influence, in chapter 4, Phil M. Haun makes a broadly generalizable argument about how powerful states can squander their multidimensional coercive advantages over weaker adversaries by treating coercion as an exercise in brute force rather than as a bargaining game. Using the case study of the 1994 Kuwaiti border crisis between the United States and Iraq as a illustrative example, Haun demonstrates how, by failing to modify their
own behavior in response to target concessions, strong states provide (weaker) targets no incentive to sustainably modify their behavior, leading to coercion failure, even by the most powerful of states. In such cases, states may accept coercion failure as the price for an ongoing, successful containment strategy.
In chapter 5, Alexander B. Downes explores the puzzle of why compellent threats that demand foreign leaders concede power seem to succeed so often. Drawing upon data from the Militarized Compellent Threat (MCT) data set, Downes argues that demands for regime change succeed so often (about 80 percent of the time) because, historically, such threats have largely been made against highly vulnerable targets, namely when the coercer possesses crushing material superiority, is geographically proximate to the target, and the target is diplomatically isolated. However, Downes cautions that before one concludes that regime change is easy, one should keep in mind that the conditions that made regime change successful in the past are not features of most recent attempts to persuade foreign leaders to step down. Thus in an era in which leaders have grown more willing to issue such demands, they have grown correspondingly less likely to engender the desired response and coercive success.
Coercion and Nonstate Actors
Since the end of the Cold War, ongoing civil wars have outnumbered interstate wars by about 10 to 1. More people died in terrorist attacks in 2014 than ever before, and Americans regularly identify terrorism as the most critical threat to the nation. Nonetheless, we lack critical tools to understand and address issues associated with the violence perpetrated by nonstate and substate actors because the vast majority of existing studies still focus on states coercing other states. The chapters in this section help address this lacuna by exploring how states can coerce terrorists and insurgents via drones and state sponsors, as well as how insurgents themselves effectively coerce governments.
In chapter 6, Keren Fraiman explores “transitive compellence,” a method of coercion whereby states that seek to affect the behavior of violent nonstate actors (VNSAs) do so by targeting the states that host them. The expectation is that the real and threatened costs imposed by the coercer on the base state will then persuade the coercee to crack down on the VNSAs, leading to their containment within, or forceful eviction from, the base state. Fraiman argues that this trilateral brand of coercion is both more common and more effective than is generally recognized. This is because the conventional wisdom regarding base state capabilities and motivations—that they are both too weak and too reluctant to take effective action against VNSAs—is wrong. Rather, many base states are in fact both capable and willing to effectively coerce VNSAs residing within their territory.
Nonstate actors are themselves often practitioners of coercion, rather than simply its targets. In chapter 7, Peter Krause explores the question of what
makes nonstate coercion by national movements and insurgencies succeed or fail. The balance of power within a movement drives its outcome, Krause contends, and groups’ positions within that balance of power drive their behavior. Although all groups prioritize their organizational strength and survival, hegemonic groups that dominate their movements are more likely to pursue the shared strategic objective of regime change and statehood because victory moves them from the head of a movement to the head of a new state. The hegemonic group’s dominance enables its movement to successfully coerce the enemy regime by delivering a single clear, credible message about its objective, threats, and guarantees that is backed by a cohesive strategy. Krause demonstrates the viability of his generalizable argument with a longitudinal analysis of the Eritrean national movement and its decades-long insurgency against the Ethiopian government from 1960 to Eritrean independence in 1993.
In chapter 8, James Igoe Walsh evaluates the efficacy of drones as instruments of deterrence and compellence, especially in the context of counterinsurgency operations. Drawing upon evidence from a variety of theaters, including Pakistan, Afghanistan, and Iraq, Walsh argues that the use of drones can be a double-edged sword. On one hand, they offer noteworthy technological, force-protection-related, and collateral-damage-limiting advantages. On the other hand, the employment of drones often also catalyzes retaliatory and signaling counterattacks by insurgents and other VNSAs, which can in turn exercise deleterious effects on counterintelligence campaigns and undermine efforts at coercion.
Domains and Instruments Other than Force
State-to-state coercion still dominates the headlines, but it has increasingly taken on new forms and is transpiring in new domains. The United States is actively sanctioning Russia and China in response to increasing cyber attacks. The European Union (EU) and many Middle Eastern states are struggling, even teetering, under the political and economic weight of an unprecedentedly large influx of migrants and of refugees forced from their homes. At the same time, regional powers are scrambling to coercively compete over natural resources in the Arctic and the South China Sea. The chapters in this section provide powerful new theories and frameworks to explain how states coerce others using often effective, but understudied, instruments other than force.
In Chapter 9, Jon R. Lindsay and Erik Gartzke analyze the relationship between cyber means and political ends, an issue that was long neglected in the popular focus on technological threats. The authors present typologies of potential cyber harms in terms of costs and benefits and of political applications of these harms for deterrence and compellence. They then use the latter to explain why the distribution of the former is highly skewed, with rampant cyber frictions but very few attacks of any consequence. Specifically, they propose that a variant of the classic stability-instability paradox operates to constrain cyber conflict: ubiquitous dependence on cyberspace and heightened
potential for deception expand opportunities to inflict minor harms, even as the prospect of retaliation and imperatives to maintain future connectivity limit the political attractiveness of major harms.
In chapter 10, Kelly M. Greenhill explains how, why, and under what conditions (the threat of) unleashing large-scale movements of people can be used as an effective instrument of state-level coercion. This unconventional yet relatively common coercion-by-punishment strategy has been used by both state and nonstate actors as a tool of both deterrence and compellence. After outlining the precepts of the theory, Greenhill illustrates this unconventional instrument in action with a longitudinal study of its serial use by the former Libyan dictator Muammar Gaddafi against the EU, from 2004 until his deposition in 2011. The chapter concludes with a discussion of theoretical and policy implications, observations about how this tool appears to be used increasingly as an alternative to or complement of military force, and what such developments might portend both for the future and for its real victims, the displaced themselves.
Timothy W. Crawford further expands our understanding of the dynamics of coercion in chapter 11 with the introduction of the concept of “coercive isolation.” Coercive isolation refers to an oft employed but undertheorized nonmilitary instrument of coercive diplomacy that relies on manipulation and exploitation of shifts in a target state’s alignments and alliances to influence its cost-benefit calculations and, by extension, the probability of coercive success. After presenting the theory of coercive isolation and the logic that undergirds it, Crawford offers a plausibility probe of six historical cases, from before World War I through the end of the Cold War, that illustrate the logic of the model and its key propositions. The chapter concludes with a discussion of contemporary theoretical and policy implications of the role played by coercive isolation in diplomacy in the post-post–Cold War world.
In chapter 12, Daniel W. Drezner examines the state of the literature on the coercive power of economic sanctions, with a particular emphasis on the use of targeted sanctions. Drezner argues that the development of smart sanctions has solved many of the political problems that prior efforts at comprehensive trade sanctions created. In many ways, these sanctions are, as advertised, “smarter,” but there is no systematic evidence that smart sanctions yield better policy results vis-à-vis the targeted country. When smart sanctions work, they work because they impose significant costs on the target economy. It would behoove policymakers and scholars to look beyond the targeted sanctions framework to examine the conditions under which different kinds of economic statecraft should be deployed.
In chapter 13, Jonathan N. Markowitz asks why some states coercively compete militarily over the governance and distribution of natural resources, while others favor reliance on market mechanisms. In this hypothesis-generating contribution, Markowitz argues that the choices states make lie in their domestic political institutions and economic interests, which in turn determine their foreign policy interests. Specifically, he posits that the more economically
dependent on resource rents states are and the more autocratic their political institutions, the stronger their preference to seek direct control over stocks of resources. Conversely, the less economically dependent on resource rents states are and the more democratic their political institutions, the weaker their preference to directly control stocks of resources. He presents and demonstrates the viability of his argument using a combination of deductive theorizing and historical analysis of recent jockeying over control of maritime seabed resources in the East and South China Sea, Arctic, and Eastern Mediterranean.
Nuclear Coercion: Regional Powers and Nuclear Proliferation
The field of coercion studies was founded on the analysis of nuclear weapons in the Cold War, and yet a number of related dynamics remain unexplained as a consequence of the field’s traditional focus on strong states that already possess nuclear weapons. The chapters in this section focus on two types of significant coercive threats by relatively weaker states: the threat of nuclear weapon use to resist demands and ensure regime survival, and the threat of acquiring nuclear weapons to compel concessions.
In chapter 14, Jasen J. Castillo examines how the acquisition and threatened use of nuclear weapons can be utilized by weaker states to resist the demands of their more powerful counterparts. The uniquely destructive power of these weapons allows conventionally weak states a method of guaranteeing their survival and, due to the dangers of escalation, a potentially potent countercoercive tool. Employing an explicitly neorealist perspective, Castillo explores not only how regional powers may use such weapons as a powerful deterrent but also how they might theoretically employ them in war should deterrence fail.
In chapter 15, Tristan Volpe explores how states can use the threat of nuclear proliferation as an instrument of coercion. He argues that while the conventional wisdom suggests states reap deterrence benefits from nuclear program hedging, many use the prospect of proliferation not to deter aggression but as a means of compelling concessions from the United States. Some challengers are more successful than others at this unique type of coercive diplomacy, however. When it comes to cutting a deal, Volpe argues, there is an optimal amount of nuclear technology: with too little, the threat to proliferate is not credible, but if a country moves too close to acquiring a bomb, a deal may be impossible to reach since proliferators cannot credibly commit not to sneak their way to a bomb. Volpe draws upon the cases of Libya and North Korea to demonstrate the power of his theory in action.
Conclusion
The concluding chapter by Greenhill and Krause underscores the volume’s key findings and their theoretical import, identifies policy implications and prescriptions highlighted by the contributions to the volume, and points to unanswered questions and directions for further research.
PART I Coercion A Primer
An Analytical Overview
robert J. art and Kelly M. Greenhill
Just as the cold war spawned a great deal of scholarly study about deterrence, so too has the unipolar era spawned a great deal of study of compellence.1 The Cold War featured a nuclear standoff between two superpowers, one in which the survival of both countries was thought to be at stake. It is not surprising that deterrence of war, the avoidance of escalatory crises, and the control of escalation were paramount in the minds of academic strategists and politicalmilitary practitioners during this period. The bulk of the innovative theoretical work on deterrence, especially nuclear deterrence, was produced from the late 1940s through the mid-1960s. Most of the creative works during the subsequent years were, and continue to be, refinements of and elaborations on those foundations.2
With the advent of the unipolar era, the United States found itself freed from the restraints on action imposed by another superpower and began more than two decades of issuing military threats against or launching conventional military interventions into smaller countries, or both: Iraq (1990–91), Somalia (1992–93), Haiti (1994), North Korea (1994), Bosnia (1995), Kosovo and Serbia (1998–99), Afghanistan (2001), Iraq again (2003–11), Libya (2011), Syria (2014–), and Iraq yet again (2015–). Unsurprisingly, strategists and practitioners during the unipolar era became focused on various forms of compellence— compellent threats, coercive diplomacy, and the limited and demonstrative uses of force—and especially on the reasons those forms of compellence, when employed by the United States, more often than not failed and subsequently
1 We thank Victoria McGroary for invaluable research assistance.
2 For an excellent overview of the state of knowledge about deterrence through the 1970s, see Robert Jervis, “Deterrence Theory Revisited,” World Politics 31 (1979): 289–324. For a representative view of the nature of deterrence today, see Patrick M. Morgan, “The State of Deterrence in International Politics Today,” Contemporary Security Policy 33 (2012): 85–107.
required more robust military action for the United States to prevail. As a consequence of the unipolar era’s change of focus, the literature on compellence burgeoned.3
More recently, and particularly in the aftermath of the game-changing terrorist attacks on September 11, 2001, there has also been a heightened focus on nonstate actors (NSAs). Academic works have focused on how NSAs employ coercion against states and against other NSAs (see, for instance, chapter 7); how states can most effectively deter and compel NSAs (and how such strategies may differ from coercion wielded by states; see chapter 6); and how NSAs attempt to compensate for their relative weaknesses through the use of asymmetric means (see chapters 8–10). In this period, there has been a nearly simultaneous increase in the nuance and breadth of scholarship that examines how coercion works when using tools other than (or in addition to) traditional military force and by actors other than the unipole. Such tools include targeted sanctions (see chapter 12), cyber weapons (see chapter 9), migration or demographic bombing (see chapter 10), and drones (see chapter 8). There has also been a growth in research that examines how coercive tools in one domain (for instance, cyber) can be used to influence outcomes in another (for instance, military capabilities), which Erik Gartzke and Jon Lindsay refer to as crossdomain coercion.4
While not providing a comprehensive review of all the theoretical and empirical scholarship on deterrence and compellence to date, this chapter does highlight the big findings about coercion, and by extension the big gaps in our understanding of it, as well as summarizes the contributions that the essays in this volume make to our understanding of coercion. The chapter proceeds as follows: Part one briefly defines coercion to include both deterrence and compellence, and shows why it can be hard to distinguish between the two in practice. Part two highlights salient points about deterrence, distinguishes among four types of deterrence, and discusses why deterrence can fail. Part three outlines the key contributions to our understanding of compellence that the past three decades of scholarship have revealed. Finally, Part four concludes with two sets of propositions about coercion—one that summarizes the state of our current collective knowledge and one that highlights new contributions proffered in this volume.
Coercion
Coercion is the ability to get an actor—a state, the leader of a state, a terrorist group, a transnational or international organization, a private actor—to do something it does not want to do. Coercion between states, between states and nonstate actors, or between nonstate actors is exercised through threats or
3 For a partial list of works on compellence, see note 18.
4 Erik Gartzke and Jon Lindsay, eds., Cross-Domain Deterrence, unpublished manuscript.
through actions, or both, and usually, but not always, involves military threats or military actions. Threats can be implicit or explicit. Coercive action may also utilize positive inducements. Offering such inducements may increase chances of success, but coercion is not coercion if it consists solely of inducements. Coercion always involves some cost or pain to the target or explicit threats thereof, with the implied threat to increase the cost or pain if the target does not concede.
The Two Faces of Coercion
Coercion comes in two basic forms: deterrence and compellence. Often the terms coercion and compellence are used interchangeably, but that erroneously implies that deterrence is not a form of coercion. This chapter therefore reserves the term coercion for the broad category of behavior that can manifest as either deterrence or compellence.
Used this way, deterrence is a coercive strategy designed to prevent a target from changing its behavior. “Just keep doing what you are doing; otherwise I will hurt you” is the refrain of deterrence. It operates by threatening painful retaliation should the target change its behavior. A state issues a deterrent threat because it believes the target is about to, or will eventually, change its behavior in ways that will hurt the coercer’s interests. Thus getting an actor not to change its behavior, when its preference is to change its behavior, is a form of coercion. Compellence, on the other hand, is a coercive strategy designed to get the target to change its behavior.5 Its refrain is “I don’t like what you are doing, and that is why I am going to start hurting you, and I will continue to hurt you until you change your behavior in ways that I specify.” Compellence, either through threat or action, is a form of coercion because the target’s preference is not to change its behavior, but it is being forced to do so. So deterrence is a coercive strategy, based on threat of retaliation, to keep a target from changing its behavior, whereas compellence is a coercive strategy, based on hurting the target (or threatening to do so), to force the target to change its behavior. In both cases, the target is being pressured to do something it does not want to do.
Is It Deterrence or Compellence?
Defining the analytical distinction between deterrence and compellence is easy; applying the distinction in practice can be more difficult, for two reasons. First, in confrontational situations, there is the eye-of-the-beholder problem; second, particularly during crises, the deterrer may resort to compellent actions to shore up its deterrent posture.
5 Thomas Schelling coined the term compellence. See Thomas C. Schelling, Arms and Influence (New Haven, CT: Yale University Press, 1966), 71.
