1. bookVolume 5 (2019): Issue 2 (December 2019)
Journal Details
First Published
16 Apr 2015
Publication timeframe
2 times per year
access type Open Access

Extended Deterrence Dilemmas in the Grey Zone: Trans-Atlantic Insights on Baltic Security Challenges1

Published Online: 10 May 2019
Page range: 5 - 16
Received: 12 Apr 2019
Accepted: 14 Nov 2019
Journal Details
First Published
16 Apr 2015
Publication timeframe
2 times per year

Should the U.S. respond with military means to a limited Russian incursion in the Baltics? This paper explores Western attitudes towards such a hypothetical grey zone crisis. Using survey experiments and crisis simulations we find considerable reluctance to use military tools in order to support a Baltic ally, and surprisingly little variation across the audiences. The underlying reluctance to get the U.S. involved in an armed conflict with Russia in the hopes that such acquiescence may help preserve global stability indicates that the conflict in Ukraine only had a fundamentally limited impact on Western strategic thought on deterring Russia.



Continuous low-level confrontations just below the threshold of war but increasingly far away from peace (the “grey zone”) appear to be an emerging norm for competition in international relations. After years of relative stability, Europe has again become a theatre for such confrontations, with Russia turning from a prospective partner to a challenger. Hence, the need for deterrence and escalation management tools has emerged with renewed urgency, but the West is still searching for appropriate adjustments to the Cold War era doctrinal and strategic communication approaches. Furthermore, the underlying narratives about the unfolding situation, and the desired solutions to it, tend to differ in the Baltic capitals and Washington DC.

Set against the background of Baltic security realities, this study explores the American public perspectives on it, comparing them with the understanding of Western experts. This paper presents the core research insights from studies between 2015 and 2018 conducted by the ICONS Project at the University of Maryland using innovative methods to study these unfolding phenomena, namely a large-n U.S. public survey experiment, and two expert elicitations via online simulations.

Our findings suggest considerable reluctance of the U.S. public to use the military in order to support a Baltic ally against Russia, with national risk tolerance and policy time horizons accounting for most variation in responses. The dynamic scenarios explored in expert simulations indicate an even greater reluctance to resort to military tools, and even to use NATO channels for resolving such a crisis. These results converged across our studies, despite the variation in crisis scenarios, including the leveraging of geopolitical differences within the Baltics. This suggests that although the understanding of Baltic regional dynamics and Russian tactics is gradually advancing, there is still little appreciation in the United States for significantly different settings (particularly in terms of the extent and status of the local Russian minority), and thus different challenges in thwarting Russian grey zone influence, that each of the Baltic states presents. Moreover, the underlying reluctance to get the United States involved in an armed conflict with Russia in the hopes that such acquiescence may help preserve global stability is a sign that the conflict in Ukraine only had a fundamentally limited impact on Western strategic thought vis-à-vis deterring Russia.

Section 1 of this paper outlines the emerging definitional understanding of the U.S. defence practitioners about the dynamics of grey zone conflict. Section 2 lays out the theoretical frameworks on deterrence and escalation management shaping the current search for effective responses to grey zone crises. Section 3 reviews the key aspects of national security and defence culture in Lithuania and Latvia,

The paper focuses on Latvia and Lithuania, as these two Baltic countries seemed to experience the most serious gaps in defense preparedness prior to 2014. In addition, historically, the Western publics seem somewhat more familiar with the developments in Estonia and it is frequently chosen as a single regional case study; as the discourse concerning the other two Baltic states was rapidly gaining in intensity, it was interesting to see whether greater familiarity would be developed.

with emphasis on the post-Ukraine changes in these two NATO eastern border states subjected to intense Russian grey probing tactics. Section 4 details the multiple methodological approaches utilized in investigating the U.S. public and expert attitudes towards defending NATO’s eastern borders in hypothetical crisis scenarios.

Defining Grey Zone Conflict

In terms of defining the grey zone, several studies (e.g. Bragg, 2016) have found it to be a kind of “you’ll know it when you see it” phenomenon. Generally, grey zone conflict is understood to be a confrontation that has moved beyond acceptable competition, but has not yet evolved into direct conventional conflict in between war and peace. As a confrontation continuous in time and space, it consists of a series of low-level crises the cumulative impact of which is increasingly concerning to the target state (as well as the international community). Grey zone conflict can unfold in any domain, or across domains: economic, financial, cyber, policy, and so on. It can also include the limited use of force by state proxies or non-state actors.

The key feature of grey zone conflict is the intentional choice by conflicting parties to limit the scope of engagement: they have the capability to go to war but instead they choose not to, operating under the threshold of war. The core attributes that mark grey zone activities include the use of ambiguous actions that cloud or hide the identity of the actor, use of multiple sources of national power in multiple arenas, on multiple and variable time scales, and challenges to international rules and norms (gradually eroding or directly countering them). Significantly, grey zone is conditioned by context, intent, and the perception of the action’s target, giving rise to competing perspectives: we are already at [grey zone] war and should act accordingly versus we are doing our utmost to avoid [full-scale military] war.

In terms of classical deterrence theory, grey zone conflict can be characterized as low-level brinksmanship, testing a defender’s commitment before further escalating to a substantive status quo challenge (George and Smoke, 1974). Grey zone conflict is also consistent with the stability–instability paradox: the greater the emphasis on successfully deterring an all-out war, the more prevalent low-level conflict becomes (Snyder, 1965). Probes arise when the defender’s commitment is in question (not necessarily because the challenger has already committed to a fight), so that a counter-threat can be sufficient to make the challenger retreat (Huth and Russett, 1990).

Continuous engagement in low-level confrontations might emerge as the new status quo for Western democracies (Desch, 2008), and domestic audiences are less likely to support military action when facing non-existential crises (Thomson, 2016). After more than two decades of uneasy cooperation, NATO is again facing a challenge from Russia in Eastern Europe in the form of a series of recent low-level incidents. These confrontations appear to be designed to remain below the threshold of articulated or implicit “red lines”, and certainly below overt military-on-military conflict that would trigger a NATO collective security commitment under Article 5. Incidents such as “using semi-formal nuclear threats to support covert sub-conventional interventions” (Krause, 2015) or “obfuscating the nature of local crises fomented from without” (Lanoszka, 2016) are becoming increasingly common. Before delving into the specific manifestations of grey zone pressure tactics in the Baltics, and the preferred Western responses to this challenge, The following section highlights several key theoretical elements shaping the current U.S. approach to allied support, in terms of extended deterrence and escalation management in grey zone crises.

Classic Deterrence and Grey Zone Warfare

Deterrence research has traditionally focused on exploring strategies that prevent interstate conflict, analysing the role of threats issued and/or acted upon towards that objective. The body of scholarship on deterrence can be roughly divided into four waves based on its key focal points and methodological approaches.

Excellent summaries of the latest advances in the field are provided by Zagare and Kilgour (2009), Signorino and Tarrar (2006), and Quackenbush (2011).

Exploring state-to-state level conflict, the first wave of deterrence research laid the theoretical groundwork for the role of nuclear weapons in U.S. national security in the immediate aftermath of World War II. The second wave (1950–1960s) focused on refining the deterrence logic through game theory and addressed the balancing of threats to challengers with assurances to protégés. The third wave (1970–1980s) emphasized empirical assessment of the classical model and its extensions (case studies and statistical methods), finding significant limits in the scope or empirical validity of deterrence theory. The fourth wave of deterrence studies has started to grapple with problems inherent in the traditional “deterrence equation” setup: empirical research has focused on deterring non-state actors (as opposed to states); and theoretical developments have introduced concepts like learning, and unpacked the elements of credibility, using new methodologies (Knopf, 2010; Lupovici, 2010; Quakenbush, 2011). Building on the theoretical underpinnings of the fourth wave, this study uses research survey experiments and expert elicitations in the form of crisis simulations/methods not yet applied to studying extended deterrence dilemmas. It seeks to understand the current thinking of U.S. experts and publics towards a returned and re-imagined problem of defending European allies against Russia, though in an increasingly limited type of confrontation.

Classical deterrence theory addresses actions at opposite nominal ends of the spectrum of conflict behaviour: credibly signalling willingness to engage in ultimate levels of violence in order to maintain a peaceful status quo. Threats and/or actions can be used to signal the punitive measures that would follow (punishment) an unacceptable level of challenger aggression, or the prohibitive costs the challenger would incur (denial). Deterrence theory portrays escalation management as a ladder where, on a lower rung, challenger threats to the protégé are matched by defender counter-threats, and on a higher rung, challenger actions are matched by defender counter-actions.

In addition to the issuing of verbal ultimatums, the concept of threat tends to include economic, diplomatic, and other means of pressure, and some even treat limited military action as a threat (Gochman and Maoz 1984; Danilovic, 2001).

While threats and actions are treated as distinct rungs of this ladder, their deterrent role tends to be treated interchangeably and their definitions overlap. At any given point, defender’s options are presented as binary – “counter” (the challenger’s action or threat) or “abandon” (the protégé). In the grey zone, however, a challenger resorts to action straight away in the form of a low-level probe; thus, general deterrence has already failed and escalation management tools are the ones to focus on.

Existing literatures on escalation management and deterrence do not address the trade-offs between, or offer prescriptions for, a defender’s optimal choice of threats and/or actions. What does one do when an adversary’s actions fail to reach critical thresholds triggering a formal military response? Under what circumstances would the U.S. public support military action prefer to double down on the challenger in response to grey zone activity? What are the methods of choice among military, civilian, and academic experts?

In an extended deterrence setting, a revisionist power is most likely to challenge the status quo by threatening the defender’s protégé. The defender could then decide to defend or abandon the protégé, returning to the status quo ante if the defence is successful.

Considerable controversy exists over whether certain threats are deterrence or compellence, reflecting some of the ambiguity in the basic conceptual distinction between the two. Here, we consider a more timely (immediate) threat following from general deterrence failure to be immediate deterrence, since the quid pro quo is status quo ante.

If defence fails, the challenger could escalate further, moving from threats to actions. The defender would then be faced with a second iteration of its basic choice – to protect or not – until either the challenger or defender prevails. As such, grey zone conflict divides up the “all or nothing” quality of classical deterrence theory, creating the opportunity for salami-type tactics in which aggression is incremental. We modify this basic framework to better reflect other dynamics of grey zone crises (see Figure 1). For example, in a grey zone crisis, challengers tend to use threats and limited probes interchangeably, treating them as the same rungs of an escalation ladder. The defender’s choices between counter-actions and counter-threats need to be considered as well. We also need to expand the defender’s choices beyond the binary extremes of abandoning the protégé or taking up arms on their behalf.

Figure 1

Deterrence Mechanism in Grey Zone Crisis.

Defence of an ally could come in the form of a counter-threat. Issuing an ultimatum to the challenger in the hopes of avoiding a clash altogether, rather than opening fire immediately, would, in effect, mean engaging in extended immediate deterrence. A counter-threat strategy allows the defender to retain peace and to control the escalation process. The defender can decide later whether to follow through on its deterrent threat (proceeding to full-scale conflict) or to abandon the protégé after all.

A small state protégé, whose very survival might be at risk, may be myopically inclined to equate a counter-threat with abandonment. However, the global power defender tends to operate under a longer time horizon, including the prospect of repeated interactions with the challenger, and must therefore use a more nuanced reaction scale.

If the challenger’s commitment to conflict is weak, such an ultimatum ought to suffice to conclude the limited probe. Otherwise, ostensibly regardless of the outcome of the limited probe, the counter-threat gives all participants in the dispute additional time to prepare for a more substantial engagement. Doing so puts the defender at an initial disadvantage (the challenger is unopposed), but could allow the defender to mount a more substantial, coordinated defence later. Implicitly placing a premium on longer-term objectives rather than on the battle at hand effectively leaves the protégé to absorb the bulk of the costs and consequences of conflict in the short term.

If defence does come in the form of counter-action by the defender, there is a temporal perspective to consider (i.e. forces available immediately vs. eventually), and different types of actions to choose from (military vs. non-military).

In our research experiment, we focus on military actions, in order to zero in on a meaningful comparison with the option of counter-threats we introduce.

Counter-action means abandoning deterrence and sending in the defender’s local troops to fight the challenger without additional warning. This implies assigning a premium to the immediate battle at hand over uncertain prospects of a larger conflict in the future. Such a strategy increases the defender’s chances of winning the current confrontation, and also signals the defender’s commitment to the protégé. However, the initiative to escalate or de-escalate reverts to the challenger, and thus the strategy carries a risk of breaking out a broader war, which could ultimately prove much more costly. Cognitive biases, imperfect information, and distorted signals have considerable power to move the crisis in either direction.

Repeated exposure to grey zone crises, particularly those involving non-core national interests or allies – rather than the nation itself – desensitizes the electorate to the problem, and reduces the appetite for military responses. Such public sentiment also translates to the reluctance of decision-makers to respond forcefully to grey zone crises: desire to retain constituent support has been found significant in both democratic (Bueno de Mesquita, Morrow, and Zorick, 1997) and autocratic governments (Jo and Thomson, 2013). The following section details the policy and public opinion shifts in two Baltic states – Lithuania and Latvia – in response to increasingly intense exposure to Russia’s pressure through grey zone confrontation, and presents the prevalent U.S. sentiment on the matter.

Grey Zone Warfare and Lithuanian Security Concerns

Since regaining its independence from the Soviet Union in the 1990s, Lithuania has existed in constant fear of another Russian invasion, yet has paradoxically failed to evolve a mature public discourse on security and defence issues. Lithuania’s foreign policy has consistently been geared towards shoring up allied support to deter potential Russian aggression so that Lithuania has come to be viewed as a one-issue state. Having joined NATO and the European Union (EU) in 2004, the public, as well as expert, sentiment in Lithuania was that its security has effectively been taken care of, with particular hopes pinned on U.S. security guarantees (Bumiller, 2002; Šlekys, 2015). Despite having been born out of the Baltic “singing revolutions”, original narratives of the newly independent nation have for a long time revolved around civil resistance as the primary means of defending the state sovereignty, with armed forces serving as a mere tripwire (Šlekys, 2015). Still, nearly two decades later, close familiarity with and alertness to the Soviet (and later, Russian) tactics meant that Lithuanian experts were among the first to identify Russia’s information warfare as part of a greater concerning strategy, rather than a nuisance (Maliukevičius, 2005, 2007).

However, the domestic inertia was slow to turn around. Lithuania had been systematically reducing its defence spending over the 2004–2013 period, and until the crisis in Ukraine, the prevailing view was that the primary threats are socioeconomic rather than military. Even the Russian-linked cyberattack against Estonia in 2007 and Russia’s incursion into Georgia in 2008 amid the Summer Olympics in Beijing failed to impact the public perceptions of threat (Delfi.lt, 2012; Eurobarometer, 2009) or produce a shift in defence policy. The 2014 conflict in Ukraine became the wake-up call for Lithuania as much as it was for the rest of NATO. Fearing that, save for NATO membership, Lithuania might have also fallen victim to Russian aggression, the country shot up to one of the fastest growing defence budgets in the alliance, re-introduced the draft, and started an active campaign of promoting membership in a variety of armed civilian and military organizations.

However, whereas the West saw Ukraine as a watershed marking the return of discourse about tactical nuclear use and thus the end of nuclear arms reductions in Europe, Lithuania focused largely on the elements of grey zone tactics on display. Discussions focused on the use of “little green men”, cyber offensive tools, and disinformation campaigns. In addition, whereas the West seemed to accept Russia’s imposed notion about ambiguity of the unfolding events, Lithuania continued to call it war (eventually, Western discourse on Ukraine has moved towards acknowledging this may be considered war from Ukraine’s perspective, but still treating it as a grey zone crisis from the perspective of the West). Fearing that Russia’s expansionist campaign might gain momentum, experts pointed to the growing number of Baltic airspace violations by Russian aircraft flying without transponders (Milne, Jones, and Hille, 2014) and the aggressive nature of Russia’s military exercises Zapad 2018 along Lithuania’s borders.

Lithuania also commissioned a series of research studies on public threat perceptions, attitudes towards national defence, and readiness to contribute to it, in addition to stepping up defense spending. Lašas (2016) and Janušauskienė et al. (2017) found that, after the initial scare, public opinion focus was back on the socioeconomic concerns, indicating the uphill battle for state institutions to maintain public interest in defence matters and communicate effectively. Nevertheless, Ramonaitė (2018) discovered that, based on extrapolation from the public opinion survey, up to 150,000 Lithuanians were inclined to participate in armed defence of the country – even though state institutions remain ill-equipped to effectively use such civilian support. The sense of national pride was the most significant factor driving this readiness to supported armed resistance. It is interesting to note that, in contrast to the discourse in the West, the framework of deterrence and the effectiveness of different tools of ensuring it have not received a lot of attention in Lithuania. Instead, the discourse is primarily framed as increasing the readiness for armed and civilian resistance.

Grey Zone Warfare and Latvian Security

Despite being seen from outside the region as the Baltic states, Latvia and Lithuania could hardly be more different. Whereas the highly ethnically uniform Lithuania has been vocally anti-Russian, Latvia has been considerably quieter on this issue, concerned about potentially alienating the nearly quarter of its population who are ethnically Russian. Historically, Latvia’s Russian population has been split between two extremes: the poor of the rural Latgale region and the influential businessmen and policy makers of the capital Riga. Leanings of these significant segments of the electoral spectrum have meant that Latvia’s policy towards Russia has been the most accommodating of the three Baltic states (Beitane, 2015), with a prevailing view that Russia has no expansionist ambitions towards the Baltics and that it is NATO expansion that may be provocative.

The 2014 conflict in Ukraine marked a turnaround point for Latvia’s security concerns as well, though with a different tone. Russia’s benevolence has been increasingly questioned, though an invasion is considered a very low-probability event (contrasting with Lithuania’s rhetoric of an imminent threat), and there was no return to conscription despite an increase in defence spending. Indeed, Latvia has focused mostly inwards, trying to understand the extent of Russia’s influence on, and appeal to, the local minorities (Rostoks and Vanaga, 2016) before they become a tool in grey zone confrontation. Latvia has directed significant research efforts towards a better understanding of concerns of the local Russians whereas Lithuania’s main interest has been in the public’s readiness for total defence, with a propensity to dismiss concerns of local Poles or Russians as irrelevant.

One consistent concern has been the significant penetration and popularity of the Russian media in Latvia – this was reflected in emerging research, and also led to the establishment of NATO’s Strategic Communications Centre of Excellence in Riga in January 2014. Indeed, in attempting to counter this type of Russian influence, in some views Latvia has overstepped the bounds when it suspended the broadcasting of Russian television channels most closely associated with pro-Kremlin narratives – Sputnik and RTR – attracting considerable EU criticism for heavy-handedness. Overall, the appeal of Russian-spun narratives in Latvia seems to be gradually declining, as indicated by a 2017 opinion poll: the two narratives most actively promoted by pro-Kremlin sources – that NATO is a threat to Russia and that Russians are being discriminated in Latvia – had limited popular appeal, as 68% of Latvians disagreed with the first statement and 74% with the second one (including 51% of Latvia’s Russian speakers) (Latvijas Fakti, 2017).

U.S. Views on Baltic Security

In the face of increasingly bold Russian grey zone confrontations, the ambivalence of Western experts and the general publics of NATO member states towards defensibility and even defence-worthiness of the Eastern Europe became a major source of concern in the Baltics. The 2015 Pew poll of Western publics showing reluctance to defend NATO’s Baltic states in the case of Russian aggression (see Figure 2; Simmons, Stokes, and Poushter, 2015) came as a shock. Even more unnerving was the Rand study alleging that Russia could overrun the Baltics in 72 hours, effectively cutting off allied assistance (should it be sent in the first place) using its A2AD capabilities (Shlapak and Johnson, 2016). Boyd’s (2017) review of 12 prominent American think-tank attitudes towards Baltic security issues revealed that half of them were supportive of U.S. shoring up security commitments to this region, while the other half barely mentioned the Baltics at all. Realist attitudes that rationally calculate the Baltic to be indefensible and argue for securing global stability through great power agreements are currently pervasive in American academia, but seem lacking among think-tank experts and media commentators – which could be reassuring to Baltic audiences. However, the limited understanding of the region’s dynamics and nuanced security realities, even at the highest decision-making levels in the United States, is a cause for no lesser concern – even if this fact is often underappreciated in the Baltics. President Trump’s confusion of the Baltics with the Balkans (Porter, 2018) is perhaps the most extreme example of this. Building on the body of surveys and analysis above, we turn to a more in-depth investigation of Western, particularly American, attitudes to Lithuanian and Baltic security concerns. Instead of relying on public polling or tactical-level war-gaming, we test some of these assumptions using innovative crisis simulations methodology, described in the following section.

Figure 2

2015 Pew Public Opinion Survey Shows Disinclination to Defend the Baltics.

New Methods to Explore Preferred Responses to Grey Zone Warfare

Over the period of 2015–2018, we conducted two parallel research efforts exploring hypothetical grey zone crises scenarios involving Russia and the Baltics. The first one was a large-n (3,851 random respondents) online survey of the U.S. general public conducted over Amazon’s MTurk platform in the summer of 2015. Our choice of research experiments to test the theoretical notions of classic deterrence theory is a methodological “path less travelled” in IR. One of the classic critiques of deterrence is the so-called problem of a dog that did not bark: cases where a defender’s counter-threat was sufficient for the challenger to retreat and for the status-quo-ante to be restored rarely make the news or historical accounts, and tend to be excluded from data samples (Fearon, 1994). This challenge of observability and quantifiability becomes even graver as the crises in question move further away from the prospect of a high-stakes winner-takes-all conflict and into the grey zone of gradually mounting pressure. Thus, our decision to employ laboratory-style survey experiments was designed to address the current research limitations.

The second effort consisted of two elicitations of U.S. and European experts (37 respondents) over the ICONSnet online platform in fall 2016 and winter 2018. These crisis simulations offer some insights into the Western decision-maker logic. Historically, participant-driven online simulations have proven particularly valuable in investigating policy dilemmas where uncertainty about key variables and the prospects of unforeseen courses of action has limited the usefulness of purely quantitative models. Capturing the reactions and responses of decision-makers in this open-ended manner allows us to compare these trends with the trends of general public reactions. Comparing the outcomes of these parallel research efforts allows us to offer fresh trans-Atlantic insights into Baltic security challenges.

Public Survey Experiment: Would the U.S. Public Support an Armed Response to Limited Russian Incursion in the Baltics?

Respondents were put in a position of an advisor to a U.S. decision-maker, and presented with a scenario vignette where the United States is facing off with Russia over Lithuania. In this hypothetical scenario, there is an explosion on a Russian train crossing Lithuanian territory towards Kaliningrad, and Russia uses it as a pretext to dispatch its special forces into Lithuania under the cover of damage control. The United States has a small contingent of troops stationed in Lithuania, as part of the NATO multinational trip-wire presence, and also can call upon additional forces stationed elsewhere. In response to this Russian incursion into a NATO member state, respondents could choose to dispatch these troops to engage the Russian forces in a direct limited conflict (counter-action); alternatively, they could issue a verbal threat imploring Russia to withdraw or face a joint NATO force in a more significant war (counter-threat). The level of Russian threat, and power disparity between Russian and U.S. forces varied in the vignettes. In addition, in order to mitigate for potential inherent biases surrounding U.S.–Russia historical relations, and zero-in on the responses to grey zone conflict, half the respondents were presented with a parallel set of vignettes where the scenario was identical, but “United States”, “Russia”, and “Lithuania” have been replaced with Country A, B, and C.

We have considered a number of potential explanatory variables influencing respondent preferences for counteraction versus counter-threat. The two factors that had emerged as the most significant were risk tolerance and time patience. Respondents exhibiting a higher risk tolerance preferred to let the opponent decide whether to further escalate this crisis or move towards de-escalation and were more likely to choose counter-action strategy, sending the U.S. troops immediately to defend the Baltic ally (in line with the strategic insights drawn from the classic game of chicken) (Figure 3).

Figure 3

The 95% Confidence Interval for Change in Probability of Choosing Counter-Threat Option Based on Risk Tolerance.

In terms of time horizons, respondents with shorter time horizons, who thought it more important to prevail in the current conflict (compared with implications for future conflicts), were more likely to choose counter-action strategy. The latter finding is consistent with the classical game theory insights on equilibrium in infinitely repeated games, also known as Folk Theorem. For example, the choice of strategic actions may depend more on one’s time horizon and discount factor for current versus future actions, rather than on relative power (Figure 4; Nalebuff, 1991).

Figure 4

The 95% Confidence Interval for Change in Probability of Choosing Counter-Threat Option, Based on Time Horizons.

It is also worth noting that younger and self-identifying left-wing respondents were more inclined to send the U.S. troops in response to this crisis. This demographic picture of who might come to the Baltics’ aid today stands as an important contrast to the historical Baltic efforts to cultivate political ties with the Republican party (representing right-wing and right-leaning respondents) under the assumption that the Republicans would be more inclined to offer armed assistance in case of Russian aggression.

In addition, we have found U.S. respondents significantly more inclined to choose a counter-threat strategy and retain control over the escalation process when they were aware that Russia was their opponent. At the same time, awareness of the specific real-world status of Russia as a long-term, iterative, and re-ascendant geopolitical adversary seems to have increased the salience of time preferences. That is, when respondents faced off against Russia as an opponent, their concerns with retaining their ability to confront their opponent in the long run had a stronger effect on their choice of a counter-action. This effect is somewhat striking, given that respondents were informed in the scenario vignettes about U.S. alliance commitments. The desire to avoid future conflict through escalation control led subjects in the experiments to allow the small Baltic ally to absorb the consequences of an immediate confrontation.

The non-findings of this effort are also worth discussing, because some of the key variables suggested by classical deterrence theory – such as power disparity and the level of threat – did not turn out to have a statistically significant impact. There are a few possible explanations for this outcome. First, these two variables may have been poorly integrated with the conceptual understanding of the American general public about what U.S. decision-makers can or should do when faced with a grey zone conflict. The second possibility is that perceptions of threat may be muted in low-intensity graze on crises – a prospect with significant implications for future conflict research to consider. Finally, it is also possible that the strategic nature of the scenario may imply that the respondents could have already factored in the level of threat and power disparity.

Expert Elicitations: Dynamic Online Simulations of Crises in the Baltics

To elicit expert opinions on trans-Atlantic security dynamics concerning Lithuania, as well as other Baltic states, we used two online crisis simulations, conducted over the ICONSnet platform. Each simulation involved top-level participants from the United States and Europe, with military, government, and academic backgrounds.

The first exercise was conducted in fall of 2016, in support of U.S. SOCEUR, and involved 29 expert respondents. The scenario vignette explored a series of suspicious Russia-linked incidents against Latvia: a cyberattack against the energy grid, an explosion in a Russian-language middle school, and staged protests in Riga. As Baltic, American, and Western European experts addressed these crises, several important findings emerged. The first was that both Latvia and its neighbour Lithuania delayed asking for Western assistance as long as possible – U.S. and/or NATO assistance in handling Russian interference was likely seen as the ultimate trump card to be called upon only at the darkest hour (which any individual grey zone crisis hardly qualified as, though their cumulative impact was approaching the threshold). The problem was that it significantly complicated escalation management, depriving allied decision-makers of a series of tools that could help de-escalate the conflict early and giving rise to more possibilities for the adversary to sow discord and ambiguity among the allies. The second important insight was that the EU played a significantly more important role than NATO in managing the grey zone crises – turning to NATO resources was seen as too escalatory a step. The third significant insight was that although the experts agreed at the outset on the importance for NATO and the EU to maintain a united front, during any particular crisis there was a tendency to conduct bilateral talks with Russia, trying to resolve the situation without involving the target state (i.e. Latvia) directly – which inevitably backfired.

The second online crisis simulation was conducted in 2018, at the behest of U.S. STRATCOM, and involved eight experts from the United States and Western Europe. This time the scenario focus was back on Lithuania – Russia was conducting suspicious naval exercises in the vicinity of Kaliningrad, with the United States suspecting this to be a cover for attack preparations, followed by staged protests and media campaigns. It was interesting to note that in 4 years since the start of the conflict in Ukraine the Western expert community has become significantly more attuned to Russia’s grey zone tactics, but hardly became more aware of the Baltic security realities. For instance, a Lithuanian call for international attention to the unfolding crisis was anticipated and swiftly responded – though through nonmilitary means. Russian information campaigns were met with much more effective response, including managing communications to Western domestic publics, rather than giving in to the whack-a-mole of every false news item. However, the experts’ understanding of the size, composition, and the living conditions of the local Russian population remained limited (e.g., similar treatments were under consideration for the near-homogenous Lithuania as were previously suggested for the ethnically-split Latvia), and the simulated plights of discrimination and unfair treatment – planted as Russian disinformation campaigns – were still gaining substantial international traction. In addition in responding to international crises, experts still preferred to avoid NATO tools and mechanisms, looking for other European institutional avenues. This is curious to observe, in light of the EU-NATO cooperation agreement signed in Warsaw NATO summit in 2016; while NATO seems to be the headliner and the initiator of the search for new tools to respond to grey zone security challenges, it is the EU and other non-military organizations that possess the set of tools that seem preferred by the member states when it comes to managing escalation.


While considerable effort has already gone into exploring the Baltic security challenges, as well as U.S.–Russia deterrence relations, this study brings an important new perspective on U.S. public and expert views on the appropriateness of military responses to the grey zone security dilemmas that Eastern Europe currently presents. With a growing number of limited or grey zone probes from Russia, it is crucial that small state Baltic protégés get a better grasp on how and how much the defender understands about the pressures they face, and what course of action the defender is likely to take in an effort to defuse such security crises in the long run.

The experiments conducted in 2015 revealed three key insights. First, they showed that neither power disparity nor the level of perceived threat had any effect on the defender’s choice of a counter-action versus counter-threat strategy. Overall, the most consistent factor determining this choice was whether the experimental subject thought it more important to be able to confront the challenger now or in the future. Those who thought it more important to confront the challenger now were more likely to choose the win strategy, whereas those who thought it more important to be able to do so in the future were more likely to choose the counter-threat strategy. This finding did not depend upon whether or not the challenger was identified specifically as Russia. This is consistent with the classical game theory insights on equilibrium in infinitely repeated games, also known as Folk Theorem. For example, the choice of strategic actions may depend more on one’s time horizon and discount factor for current versus future actions, rather than on relative power (Nalebuff, 1991).

Second, the experiment showed that the primary initiative concern of the defender also had a strong effect on the decision to counter-action versus counter-threat. Those subjects who expressed a preference for placing responsibility for escalation versus de-escalation in the hands of their opponent (in line with the strategic insights drawn from the classic game of chicken) were less likely to choose the counter-threat strategy than those who preferred to retain control over the escalation/de-escalation process (a preference reflecting policy-maker discretion).

Third, we have also found that U.S. subjects were more inclined to issue a warning to their opponent and retain control over the escalation/de-escalation process when they were aware that Russia was their opponent. In addition, when facing off against Russia as an opponent, the responders’ concerns with retaining the ability to confront their opponent in the long run had a stronger effect on their choice of a counter-action versus counter-threat strategy than their concerns with retaining control over the current escalation/de-escalation process. The reluctance of U.S. general public members to support direct and immediate military confrontation with Russia, even when witnessing aggressive moves against U.S. allies was striking, and the propensity to allow a smaller U.S. ally to absorb the consequences of an immediate confrontation in the hopes of maintaining global stability – indicative of the limited appeal of the historical lessons of appeasement strategy failures.

Nevertheless, the experiment also offered an important demographic revelation about the potential Baltic supporters in the U.S.. The fact that younger Democrats (an audience rarely engaged by the Baltic lobbyists, policy makers, or media) were significantly more inclined to support armed defense of the region – as opposed to Republicans, with whom the Baltics have historically cultivated a relationship – calls for a shift in this aspect of transatlantic engagement.

The key insights from the two expert elicitations conducted in 2016 and 2018 were not too dissimilar to those from the experiment, if more nuanced. The simulations revealed a limited familiarity with the Baltic security realities (particularly in terms of the ratios and relations between the local and ethnic Russian parts of the population). The inability to correctly gage, e.g., the level of adversity among the ethnic Russians to their local counterparts, their level of support for Kremlin, or even their demographic profile (urban vs. rural concentration) has tended to produce misjudgments about the extent of adversarial penetration or channels available to deal with crises in non-military means. In addition, lacking a baseline understanding for what constitutes a normal level of competition, and which crisis threatens to get out of hand added burden and confusion to the inherently slow-rolling NATO decision-making. This was made worse by the propensity of the Baltic states to delay asking for Western assistance, holding it out as the ultimate trump card and deterrent threat. It is important to note that by the second simulation, Western familiarity with the Russian use of grey tactics has increased – but it did not come with a parallel increase in understanding of the distinctiveness of the sociopolitical and ethnic backgrounds in the two Baltic states against which it unfolded.

Similar to the U.S. public, experts from the United States and Western Europe were systematically reluctant to employ military tools to address grey zone crises in the Baltics – either bilaterally or through NATO. Although the Baltics tended to view such crises as an inevitable antecedent to Russian territorial expansion – something NATO was designed to deter – Western experts viewed any retaliatory use of NATO tools as escalatory, and preferred to handle grey zone crises through EU channels. In the context of revived discussions about the feasibility and need for European security forces independent of NATO or the United States, these insights should serve as a sobering reminder of the limited appetite for military engagement on the continent.

These insights can be viewed in the broader context of grey zone conflict, which is likely to typify competitive interactions between major power adversaries in the future. Whether we are talking about the United States or NATO versus Russia, or a potential conflict involving China, we are confronted today with a new international order and faced with the necessity of new mechanisms for reducing the risks of escalation. New thinking on managing escalation in extended deterrence settings may be one of those mechanisms that will prove useful in combatting grey zone conflict in this new environment.

Figure 1

Deterrence Mechanism in Grey Zone Crisis.
Deterrence Mechanism in Grey Zone Crisis.

Figure 2

2015 Pew Public Opinion Survey Shows Disinclination to Defend the Baltics.
2015 Pew Public Opinion Survey Shows Disinclination to Defend the Baltics.

Figure 3

The 95% Confidence Interval for Change in Probability of Choosing Counter-Threat Option Based on Risk Tolerance.
The 95% Confidence Interval for Change in Probability of Choosing Counter-Threat Option Based on Risk Tolerance.

Figure 4

The 95% Confidence Interval for Change in Probability of Choosing Counter-Threat Option, Based on Time Horizons.
The 95% Confidence Interval for Change in Probability of Choosing Counter-Threat Option, Based on Time Horizons.

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