This article is part of the contribution made by the US Army War College to the series “Compete and Win: Envisioning a Competitive Strategy for the Twenty-First Century.” The series endeavors to present expert commentary on diverse issues surrounding US competitive strategy and irregular warfare with peer and near-peer competitors in the physical, cyber, and information spaces. The series is part of the Competition in Cyberspace Project (C2P), a joint initiative by the Army Cyber Institute and the Modern War Institute. Read all articles in the series here.

Special thanks to series editors Capt. Maggie Smith, PhD, C2P director, and Dr. Barnett S. Koven.

The recent standoff between NATO and Russia over Ukraine has now escalated into a full-scale Russian invasion. To understand the significance of the Russian attack, it is important to remember that attacking Ukraine in a show of unprovoked aggression represents the Russians’ second worst outcome. Preferably, of course, NATO would have acquiesced to Russia’s demands regarding its near abroad. To achieve that outcome, Russia’s most dangerous courses of action were not those that would have rendered NATO incapable of responding to its provocations, but those that rendered it unwilling to do so. Prior to invading Ukraine on February 24, Russia tried to impose strategic paralysis within its perceived sphere of influence by convincing both political leaders and the publics they serve that they would be worse off if they resisted. Given the currently unresolved conflict, the United States, NATO, and its partners are still scrambling to devise an adequate response.

War is about one nation imposing its will on another; coercion is about one nation getting an adversary to accept its interests. To the extent the United States and NATO tried to shape conditions in Europe and avoid a war with Russia, they ultimately failed to convince Russia that invading Ukraine was not in its best interest. Changing minds depends largely on shaping the choices available to avoid conflict. Unlike war, where success depends on the destruction of enemy forces, coercion depends on balancing cooperation and confrontation to present an adversary with alternative courses of action that makes it worse off should it continue to challenge another state’s national interests.

Part of the problem, as Tami Davis Biddle points out, is that military practitioners fail to adequately distinguish between defeating enemies and coercing them. Military forces are designed to destroy enemy forces faster than that enemy can destroy friendly ones. When there are no enemy military forces to destroy, military forces may still have utility, but how to employ them is less clear. Clarity depends on recognizing that warfighting and coercion are two different kinds of activities, each with its own logic and grammar.

The Logic of Coercion: Imposing Wills versus Changing Minds

Carl von Clausewitz famously distinguished between war’s logic and its grammar, pointing out that while war shared a logic with politics, it had “a grammar of its own.” As Antulio Echevarria points out, logic is expressed in terms of imperatives, principles, or procedures that govern an activity while grammar refers to those principles, rules, or procedures that govern the use of force. Failing to align the two, Clausewitz further argues, is much like knowing enough of a language to say a few phrases but not understanding a language’s nuance and sometimes saying something unintended.

Because both war and coercion serve political ends, many assume they share a similar logic. However, there is a difference between the kinds of objectives pursued in war and the kinds pursued in competition. As political scientist Patricia Sullivan argues, “brute force” objectives and “compliance” objectives are different: in war, political and military objectives, while not identical, are closely linked and victory is achieved through brute force objectives, like the destruction of military forces or seizure of territory or resources. When the enemy’s army is destroyed, the war is won. Compliance objectives, on the other hand, are achieved by changing opponents’ minds about what is in their interests. Because compliance objectives involve changing others’ minds, the initiative belongs to those who are the target of the coercion, who gets to decide how much punishment they will bear.

Accepting another state’s interests, of course, does not entail agreement with those interests. The target nation only has to believe that opposition to its adversary’s interests is not the best alternative available. Viewed in this manner, successful coercion is not simply about imposing costs. Instead, it is about cornering an adversary into a position where it is forced to act and that its most rational option is the one that is most beneficial to the coercing state. The distinction between imposing will and accepting another’s will is important and is far from new. The Cold War scholar Thomas Schelling highlighted a similar distinction in his influential book, Arms and Influence, by pointing out the difference between brute force and coercion. As he observed, there is “a difference between taking what you want and making someone give it to you.” So rather than wielding power to destroy, coercion is about wielding power to harm.

Schelling continues by arguing that coercion comes in two forms: compellence and deterrence. Compellence is a nation’s efforts to compel an adversary to act in a specific manner while deterrence is a nation’s efforts to prevent an adversary from acting in the first place. The two terms are related and often hard to distinguish for two reasons. First, deterrence can look a lot like compellence. Threatening actors to deter any challenge to the status quo in effect compels them to accept the way things are. To the extent that the status quo works against the challenger’s interest, any deterrent action may be interpreted as provocation and therefore as an act of compellence. Second, compellent actions are often employed by a state, especially in a crisis, to enhance its deterrent posture. For example, President John F. Kennedy’s blockade of Cuba during the Cuban Missile Crisis had both deterrent and compellent effects. The blockade was intended to not only prevent more missiles from coming in, but also to demonstrate how seriously the US took the presence of missiles in Cuba and its demands for their removal. As Schelling argues, the difference between deterrence and compellence revolves around the timing and initiative determined by the first mover and the state whose initiative is tested.

The Grammar of Coercion: Compellence and Deterrence

Coercion, whether in the form of compellence or deterrence, depends on both a credible and capable threat. Credibility, however, depends less on reputation and much more on whether an adversary believes it would be better off by carrying out a threat than not. Capability depends less on the amount of pain states can inflict than on how much worse off adversaries believe they are should they try to inflict pain. Given these conditions, it is easy to see why NATO and Russia failed to resolve their differences over Ukraine. Stepping back in time to just before Russia initiated its invasion, NATO’s limited interest in bringing Ukraine into the alliance meant that going to war with Russia over Ukraine would likely leave NATO worse off, even if it won. Conversely, because a Russian invasion of Ukraine would not weaken the NATO alliance or make it worse off relative to conceding to Russia’s ultimatum, the Russian threat lacked capability.

Calibrating a threat so that it is both credible and capable, and therefore effective, requires a better understanding of how compellence and deterrence work.


In adversarial competition, compellence typically begins when one actor demands something from another and threatens a punishment if its demands are not met. Interactions are zero-sum, in that a gain for the compeller represents a loss for the target and vice versa. Ultimately, compellers make a demand and the target must respond or suffer some consequence.

As political scientist Todd S. Sechser points out, it intuitively follows that the state with a military advantage should also have a compellence advantage. Coercive success is a function of the value of the demand, the probability the coercer would win if the interaction resulted in conflict, and the cost to either actor for engaging in military conflict. Therefore, in a situation where both actors value an interest equally, the more capable actor who is better able to absorb the cost of conflict should, in theory, succeed. However, the Militarized Compellent Threats data set, which contains 210 distinct cases of compellent threats from 1918 to 2001, shows that while 85 percent of threats surveyed were made by a major power to a minor power, full compliance was achieved in only eighty-seven cases, for a success rate of 41.4 percent.

Counterintuitive results appear most when future iterations of conflict are possible. Coercive success generally depends on accurately calibrating one’s demands: high demands are more likely to be rejected and low demands may not be adequate to realize one’s goals. Iterative engagements offer the stronger coercer the opportunity to assess the weaker state’s sensitivity to the human and financial costs of war. They can perform this assessment by means of separating strategies designed to differentiate sensitive from insensitive opponents. Such separating strategies requires the coercer to calibrate the demand so that strong actors reject the demand while weak actors concede. While doing so encourages coercers to open with higher demands, and thus risk a greater chance for failure, it can lead to bigger payoffs in subsequent rounds. Moreover, very strong actors may be incentivized to take bigger risks since they can better afford failure.

While high demands may reveal something about an adversary, they can incentivize weaker actors to be more resistant to conceding, even if it were rational to do so in the current round. Given a capable threat it is always rational to concede in a single-iteration interaction. However, in what Robert J. Art and Kelly M. Greenhill call the “capability-intention dilemma,” capability can be undermined if the target believes its adversary will continue to make demands. In fact, weaker actors are incentivized to resist up front to cause stronger coercers to moderate their demands. This dynamic can significantly increase the perceived cost of cooperation, making it less likely the target of coercion will concede.


Deterrence, as previously discussed, depends on the ability to signal a capable, credible threat. Classical models of deterrence, like Schelling’s, treat actors as if they were undifferentiated, where both seek to deter the other. However, sometimes actors are differentiated by their preference for the status quo. In these interactions, one actor defends the status quo while another challenges it. In the case of Ukraine, arguably Russia challenged the status quo relative to NATO and took actions to deter stronger political and economic ties between Ukraine and Western Europe and to degrade NATO’s relationships with Eastern European states, which would make them more susceptible to Russian pressure. In these cases, deterrence is “unilateral” in that only one side employs a deterrent strategy.

The differentiation between challenger and defender entails differentiation in preferences. Unlike classical deterrence, where escalation is the worst outcome for both actors, in unilateral deterrence that is only true for the defending actor. The status quo challenger, almost by definition, will prefer escalation to the status quo. Otherwise, there is no reason to pose a challenge. To prevent a challenge, the status quo defender has two options: it can either impose costs high enough that a challenge is more costly than the status quo or increase the challenger’s satisfaction with the status quo to devalue the challenge.

The first option is relatively straightforward but is not always possible and can be less rational than the second option. For example, NATO could have threatened to deploy military forces to defend Ukraine against a Russian invasion. However, it is not clear that, given the cost of war, doing so would be worth it. Moreover, strong rhetoric is unlikely to help. For deterrence to be effective, adversaries must believe not only that they are better off by employing the deterrent threat than conceding, but also that they are worse off if their opponent deploys that threat.

Fortunately, there are nonmilitary ways to make an adversary worse off. As Frank C. Zagare points out, even if challengers prefer the status quo to escalation, they may still challenge if they believe defenders’ worst outcome is war. Preferring the status quo to escalation, however, is not the same as being satisfied with the current balance of power. There is a threshold, and a challenger’s satisfaction with the status quo may be high enough that the cost of posing a challenge is not worth any perceived benefit. Simply put, challengers do not have to like the status quo, they just need to prefer it to the alternatives.

Accordingly, increasing an adversary’s satisfaction with the status quo can be an effective deterrent strategy. For example, in 2016, Jin Canrong, a close advisor to Chinese President Xi Jinping, detailed a strategy that intertwined US and Chinese interests and also established a set of alternatives to the global presence of the United States, like the Belt and Road Initiative, to eventually displace US influence, regionally and globally. By cooperating with the United States on some interests and challenging it on others, China is in a better power position than it could have been if did not cooperate at all.

However, cooperation for its own sake does not ensure deterrence success. For example, the United States recently dropped its objections to the Nord Stream 2 pipeline, which it had previously opposed because it would likely make Europe more dependent on Russian natural gas and increase Russian leverage in Europe. Now that tensions have escalated into conflict, it is clear that the cooperative measure had little effect and Germany has once again stopped its construction to impose costs on Russia.

Therefore, increasing an adversary’s satisfaction with the status quo can often come at a cost and can be ineffective, if not self-defeating. Rather, it makes more sense to establish a quid pro quo where any concession is conditioned on measures an adversary must also take to make deterrence success more likely. For example, dropping objections to the Nord Stream 2 project in exchange for limits on the numbers or types of Russian troops in Belarus and along the Ukrainian border may have made an invasion less likely since Russia would have had to further mobilize to bring its force levels to the point that an invasion would be successful. Any additional requirement to mobilize would have bought NATO additional time to respond. Knowing that NATO would have time to respond—thus potentially increasing Russia’s costs—could have further disincentivized an invasion in the first place.

Russia’s invasion of Ukraine can be seen as a failure to coerce on the parts of both NATO and Russia. While NATO clearly failed to deter the invasion, Russia failed to compel either NATO countries or Ukraine to limit their ties with one another. Given Russia’s interest in Ukraine is arguably much higher than NATO’s, deterrence likely had little chance. However, Russia arguably made a mistake in its December 17, 2021 ultimatum, in which it essentially demanded NATO accept a Russian sphere of influence in Eastern Europe, including over NATO members. By doing so, Russia not only raised the stakes, giving NATO more reason to resist, but also foreshadowed future iterations, making it more rational for NATO to bear higher costs and take greater risks than the alliance was previously willing. Resolving this impasse requires both sides to do more than simply impose costs. Either must calibrate its demands given the potential for cooperation, resistance, or defection present in the adversarial relationship. Otherwise, both sides only have escalation or concession as ways forward.

These, then, are important rules of thumb that guide adversarial interactions. Even if one side is significantly stronger, it should not make excessive demands unless it seeks to better understand an adversary’s preferences and is prepared to accept failure, at least at first. In interactions that iterate, minimizing adversaries’ fears that more demands may be forthcoming diminishes the likelihood that those adversaries will perceive their costs of concession to be increasing. To prevent challenges in the first place, it is important for an actor to convince adversaries that acting on an issued threat is its most rational response. If that is not possible, then it becomes important to find ways to decrease the value of the adversary’s challenge in the first place. Of course, there are likely times when none of those options are possible. However, knowing that enables better preparation for the inevitable conflict to come.

Dr. Tony Pfaff is the research professor for strategy, the military profession, and ethics at the Strategic Studies Institute, US Army War College. He is also a senior nonresident fellow at the Atlantic Council.

The views expressed are those of the author and do not reflect the official position of the United States Military Academy, Department of the Army, or Department of Defense.

Image credit: Government of the Republic of Northern Macedonia