Let me be clear upfront: This book is a must-read for anyone interested in bargaining, conflict, and/or deterrence. Branislav Slantchev makes a significant contribution to the literature by drawing our attention to a largely neglected aspect of crisis bargaining, that is, as a process that can alter the incentive structures of the involved parties and, most importantly, their expected payoffs from war. How can we credibly persuade opponents not to fight while also influencing them into desirable (for us) behavior? The bargaining literature generally addresses this question from an informational perspective, examining which strategies can best manipulate the opponent's beliefs about our own likely behavior. The role of bargaining moves is therefore strictly informational. The author correctly points out that a principal limitation of this tradition is the implied premise that an actor's incentives remain constant throughout the crisis. In contrast, bargaining is arguably as much about altering the opponent's and our own preferences for peace and war as it is about manipulating the opponent's beliefs about our preferences. Remarkably, this facet of crisis bargaining has eluded much of extant research. Slantchev's book therefore introduces an entirely novel formulation of the bargaining process.

To develop substantive propositions about bargaining as a process that creates and alters (rather than just communicates) commitments, the book uses game-theoretic models with one illustrative case study (the Korean War, Chapter 6). At the very outset (Chapter 1), Slantchev makes an excellent case for formal-theoretic treatments of crisis bargaining. While acknowledging the necessity to abstract away the multitude of empirical facets in order to focus on the essential features of a crisis, he also effectively rebuffs standard objections to rational choice theory. Moreover, the book is accessible to all readers, regardless of their methodological background. To be sure, his formal stylizations are at the most sophisticated level and should attract the attention of every game theorist in this area. It should be equally attractive to those less familiar with formal models, because much of technical discussion is relegated to well-organized appendices, and the narrative is clear throughout. The author carefully explains relevant game-theoretic terms and formal derivations, discusses the intuition behind them in the context of his argument, and abundantly illustrates with historical anecdotes; all of this is accomplished with unusual ease. Stylistically, then, the book should serve as a model for game-theorists who want to speak to all research communities.

At the core of Slantchev's argument is the conception of crisis bargaining through inherently costly military moves that modify the actors' (prewar) expectations about likely war outcomes. Empirically, these are classic war preparation methods used by states to turn the odds of winning a war in their favor. Precisely for this reason, they should also make war a less attractive option for the opponent: He (or she) would now face a lower probability of winning the war at a far greater level of costs, which, in turn, should make that opponent more reluctant to resist and fight. In theoretical sense, the distribution of power is therefore treated endogenously. These fundamentals are then formalized in order to analyze crisis dynamics: the likelihood that the threatener would opt for militarized moves that could escalate to war (“crisis stability”), that there will be a war if the threatener selects such a move (“escalation stability”), and, given the high prospects for war, the opponent's decision whether to challenge in the first place (“situational stability”). The expectations about likely behavior at each of these crucial decision nodes are formally derived in the author's “military threat model” (MTM), first assuming complete information and then uncertainty. There are many nuances to the MTM framework that make it impossible to present them all with full justice, but suffice it to say that, in essence, the military threats that have the property of changing expected payoffs do have a strong deterrent effect.

Through the lenses of his formal findings, the author then revisits puzzles from the alternative bargaining frameworks, such as those on costly signals or audience costs. (Note that the audience-costs argument also allows the threatener's, but not the opponent's, incentive structure to change, and moreover, the costs are strictly reputational without the effect of power redistribution—quite different from Slantchev's causal mechanism.) He also draws inferences for a number of other conflict theories. For example, addressing the link between arms races and war, Slantchev suggests that heavily armed states will be more cautious in taking militarized moves, but that there is nevertheless a greater risk of war than between lightly armed states. The latter, however, are more likely to behave aggressively during militarized crises, unless the distribution of power favors the threatener (pp. 163–73). This interesting, if somewhat counterintuitive, proposition is an excellent candidate for empirical analysis. The implications for other theories, such as those related to the balance of power and interests, already find empirical validations (albeit overlooked by the author) in the previous research. In general, Slantchev makes a rare attempt in the formal literature to discuss both the game-theoretic and empirical research. There are some oversights of the works in the latter group, though it is perfectly understandable given the author's formal-theoretic focus.

As a minor note, an introductory analytical road map would help us to navigate through different chapters, as each is rich in theoretical nuances and methodological expositions. Slantchev also improves upon some traditional concepts, but because he discusses them in unexpected places, they might easily go unnoticed. For example, his fourfold classification of the functions of coercive instruments is fascinating and relevant for discerning the potential of diverse bargaining models, and as such best served in the preliminaries, but it is not introduced until Chapter 4 (pp. 123–25). Also, while it is not a major shortcoming, I would not as easily discard the role of nonmanipulable motivations that sets the limits to how much the incentive structures can be altered even with redistributed power. The author claims that the emphasis on such factors can be “misleading” (p. 247) and “not interesting” (p. 19), but these are traditionally treated as the valuations of the issues at stake (i.e., inherent interests), which the author also acknowledges to be the third, though nonmanipulable, component of the expected payoff for war (besides the probability of winning and the costs of fighting; p. 58). Though exogenous to the bargaining model, further refinements on incorporating this third component into an analysis might resolve some “unhappy” policy implications. In this respect, Slantchev is candidly unenthusiastic about policy implications from his model: Peace is costly and militarized measures, both in terms of armaments and coercive moves, might be a necessity in order to preserve it.

As this last point illustrates, Slantchev makes a number of provocative arguments, and undoubtedly anyone interested in this area might disagree with some of them. Nevertheless, they are firmly grounded in his basic premises, giving coherence and consistency to each and all of his claims. In this respect, the reader is forced to rethink and improve upon her or his own arguments. In any event, Military Threats will educate about formal-theoretic work in an accessible manner (hence, it is highly recommended for graduate seminars), impress with many novel thoughts, and persuade a reader about the validity of the author's original approach to bargaining as a commitment-creating process. It will also provoke many follow-up discussions (if the point is debatable), further extensions (if the point is wholly convincing), and empirical tests. And, as a bonus, Slantchev's engaging style and much-welcomed wit will even lighten up the entire reading experience. To reiterate: a must-read.