Michael Kofman’s recent War on the Rocks essay spent much of its length critiquing RAND’s February report on the requirements for establishing a more robust conventional deterrent posture along NATO’s eastern flank. This report describes a series of wargames that we and a team of our RAND colleagues designed and ran in 2014 and 2015 to examine the potential results of a Russian invasion of the Baltic states. In aggregate, these games suggest that the permanent presence of a multi-brigade NATO armored force would likely be sufficient and might well be necessary to present Moscow with the prospect that such an attack would not result in a quick and inexpensive victory. Kofman asserts that our analysis represents “conventional wisdom,” but his piece repeats the most common arguments we’ve encountered since we began presenting this work to Pentagon audiences two years ago, reflecting what had been the standard thinking within the United States defense enterprise prior to our analysis.

In their most general form, these arguments are three in number:

While Russia has been willing to use force against countries like Georgia and Ukraine, there is no reason to think it would attack members of NATO.

Strengthening NATO’s defense along its eastern frontier could ultimately lead to the very conflict it seeks to prevent.

The more challenging Russian military threat to the Baltic republics would be limited “salami-slicing” incursions to which NATO would have political difficulty responding.

There are stronger and weaker formulations of these propositions, but varieties of each are put forward by Kofman. Each contains kernels of truth, but all are ultimately unconvincing. First, while an invasion of the Baltic states appears unlikely, its consequences would be so dangerous that not taking steps to deter it more robustly would be imprudent. Second, while Moscow would dislike a stronger NATO military posture in northeastern Europe and would probably increase its own military capabilities in response, the NATO forces in question would clearly not pose a significant threat to Russian security. Finally, the presence of NATO forces capable of deterring an invasion would also contribute to deterring subconventional attacks or limited land grabs by preventing Russia from backstopping these moves with intervention by substantial conventional forces as it did in eastern Ukraine.

“What, me worry?”

Kofman and a variety of other commentators suggest that the deterrent effect of NATO membership makes a large-scale Russian invasion of the Baltic states so unlikely that defending against it should not be a principal concern of the West. Given the frequency with which U.S. defense planners have both overestimated and underestimated the aggressiveness of potential adversaries in the past, this issue merits consideration.

We are less inclined than Kofman to place great store in the argument that Russia’s failure to invade the Baltic states during the past 15 years merits confidence in continued restraint. There is a long list of geopolitically significant events in history that appeared to be unlikely until they happened; as of 2013, Putin’s Russia had never invaded Ukraine.

Nonetheless, there are indeed reasons to consider such an action unlikely. Invading Ukraine — twice — was aggressive, but not as risky as attacking NATO member states. Russia has suffered considerable economic and diplomatic costs as a result of its behavior and would presumably expect much worse to follow from invading Latvia, Estonia, or Lithuania. According to a leaked document, Ukrainian President Poroshenko claimed that Putin stated Russian forces could quickly take Baltic and other Eastern European cities if he gave the order to do so, but rattling a sabre does not always indicate an inclination to kill with it.

Our operational military analysis is based not on an assumption that an invasion of the Baltic states is probable, but on the premise that it is sufficiently plausible to merit serious planning and examination of how it might play out, given U.S. interests and alliance commitments in Europe. The costs of a Russian fait accompli in the Baltics would be enormous. The price tag of the prudent steps we recommend to deter such a conflict pales in comparison with the potential costs, even if the chances of such a conflict are already low.

More fundamentally, Kofman makes the common error of recommending that decisions about military posture and capabilities be predicated on estimates of the intentions of adversaries. Predicting what one’s enemies intend or are likely to do is an exercise fraught with uncertainty. For this reason, sound force planning is predicated on identifying circumstances wherein three factors coincide:

Places and events in which the nation has important interests at stake

Actors who are pursuing objectives at odds with those interests

Situations in which those actors have sufficient military capabilities to pose a credible and consequential threat of action.

All three of these factors clearly figure in the current situation on NATO’s eastern flank. First, the security of NATO allies has been an enduring American commitment for decades. Second, Russia’s military doctrine refers to “the power potential of the North Atlantic Treaty Organization” as the first of the “external military risks” confronting Moscow. Putin’s behavior in Ukraine and Syria clearly indicate his willingness to employ military power in ways opposed to Washington’s objectives and concerns. Further, events of the last several years make it clear that Putin seeks to weaken and divide NATO to re-establish a droit de regard over states on Russia’s western periphery. Finally, our work demonstrates that Russia possesses a predominance of conventional military power in the region compared to NATO’s current posture (indeed, Kofman concedes this is “not exactly a revelation”).

All of this suggests that unless NATO’s political leadership is willing to bet Europe’s future security on its certainty that Russia will not attack NATO — a confidence hard to justify in light of the strategic, operational, and tactical realities of the situation — prudence dictates that modest steps along the lines recommended in our work be taken to shore up NATO’s conventional deterrent posture.

In other words, we stand by our original assessment:

President Putin clearly appears to distrust NATO and harbor resentments toward it. His rhetoric suggests that he sees the Alliance’s presence on Russia’s borders as something approaching a clear and present danger to his nation’s security. Aggressive acts, angry—even paranoid— rhetoric, and a moderate but real military buildup combine to signal a situation where it may be less than prudent to allow hope to substitute for strategy.

Even paranoids can have real enemies

Russia’s immensely long borders have historically proven nearly impossible to defend. For a thousand years, Russian leaders have seen themselves as facing a stark choice on how to successfully deal with aggressors. They can resist invaders on Russian soil at great cost, counting on the country’s vast expanses and the implacable ferocity of “General Winter” to ultimately devour them. Alternatively, they can create and maintain a buffer zone consisting of either imperial territory or complaisant states around the Russian heartland.

Kofman and others argue that even modestly increasing NATO’s posture along its eastern frontier will amplify Moscow’s existing fears of the West’s aggressive intentions. They predict this would at least prompt further buildup of Russian forces opposite NATO and might ultimately lead to a pre-emptive attack, per Kofman’s citation of Putin’s 2015 comment that “if a fight’s inevitable, you must strike first.”

We certainly agree that Russia would be unlikely to stand idly by while NATO reinforces its posture in Eastern Europe. As our report states, an improved NATO posture would fundamentally change the strategic picture from Russia’s point of view. This includes Moscow’s assessment of what it would take to win a serious war. Our public report failed to mention one fact that our briefings to Pentagon and European audiences emphasized. Our wargames testing the value of the enhanced NATO force pit it against a substantially larger (by 60 to 80 percent) Russian order of battle than the one in our baseline scenario. Yet even assuming this very substantial Russian response to our recommended actions, the addition of heavy NATO forces turns the situation from one in which Russian victory is likely to be quick and inexpensive into one where neither of those adjectives applies.

What of the risk that the presence of three NATO armored brigades so close to St. Petersburg might ignite Moscow’s paranoia to the point that it would undertake preventive war against NATO rather than tolerate their presence?

It is an obvious fact that a single armored division, even supported by NATO air and seapower, does not represent a credible invasion threat to the rodina. Indeed, it is not a force designed even to decisively defeat a Russian invasion. Instead, its purpose would be to deter such an attack by placing a low-cost fait accompli seizure of the Baltic states out of Russia’s reach. In this sense, it reflects traditional principles of conventional deterrence, mirroring those pursued by NATO in the 1980s to threaten a prospective aggressor with a conflict too expensive to appear worthwhile.

The Russians are at least as capable as the United States at calculating the correlation of forces. Indeed, to imagine that 15,000 NATO soldiers would march on St. Petersburg, the Kremlin would need to be profoundly out of touch with reality, in which case NATO’s incentives to strengthen its forces in the East would be even stronger. Moscow will certainly huff and puff and, as Kofman argues, may well bolster their own deployments in the Western Military District. Yet doing so would not neutralize the cost-imposing capability of the NATO forces. In the end, the presence of several NATO heavy brigades across the border will make Russian leaders uncomfortable (which is not a bad thing), but it should not drive them to panic.

Moreover, there is a noteworthy internal tension in believing that the deterrent power of Article 5 of the Atlantic Treaty, even without adequate forces to back it up, will reliably deter Russia from attacking the Baltic states while also claiming that the same treaty with those forces might be provocative enough to incite an invasion. In theory, either half of this combination, often proffered in Washington by opponents of reinforcing NATO’s posture, could be true, or both arguments might be correct to a more limited degree — a classical security dilemma. However, it strains credulity to argue that a Russia that would never otherwise seriously consider being aggressive in the Baltic region could nevertheless be easily pushed over the brink into launching a major war.

Dealing with Russian spectrum disorder

Kofman argues that regardless of any other consideration, worries about conventional deterrence are overblown because the real challenge to NATO is not an outright invasion but rather political warfare, subversion, covert operations, and salami-slicing tactics.

In fact, Russia can simultaneously present both a sub-conventional or limited threat to the Baltic states and a large-scale conventional threat, as Kofman himself seems to admit elsewhere in the article. Both are clearly within its capabilities, as are a range of possibilities in between and beyond. In Georgia, Crimea, eastern Ukraine, and Syria, Putin’s Russia has demonstrated a flexible approach for linking strategic goals to military means, and it’s not clear why it’s safe to assume its imagination would fail should it turn to NATO.

Crimea was the laboratory test case for “little green men.” If they weren’t going to work there, they weren’t going to work anywhere. Almost 60 percent ethnically Russian, enjoying only weak political, economic, and cultural ties to Ukraine, and with Russian military forces already stationed on its territory, Crimea’s rapid fall to Moscow’s fait accompli strategy was hardly surprising and in retrospect seems overdetermined.

By contrast, subversion tactics failed miserably in eastern Ukraine, as Kofman has described elsewhere. Only the arrival of Russian troops, tanks, and artillery in late summer 2014 saved separatists and their irregular Russian compatriots from defeat at the hands of Ukrainian security forces. It was heavy green metal, not little green men, that saved the day for Russia in the Donbas and that continues to stymie Kyiv’s efforts to restore its writ there.

Kofman argues that because eastern Estonia and Latvia are less fertile ground for “hybrid” warfare than eastern Ukraine, Russia would not use the same playbook. Instead, he argues, it is more likely to expect a scenario in which “Russia deploys a large land force on the borders as part of a snap exercise, as it did opposite Ukraine in early 2014, and then seizes some unknown patch of dirt.” Kofman continues:

Would NATO attack this offending Russian force over a few square meters? It’s one thing to contemplate trading Washington for Vilnius — what about some farm house on the Russian-Estonian border?

Since, in his view, NATO would be unlikely to mobilize just to push the Russian military a few meters back into Russia, the credibility of Article 5 would be shattered. Kofman implies that our recommended changes to NATO’s posture would be unhelpful in dealing with such a limited threat. Given the events of 2014, we disagree. Should Russia attempt and fail to slice off a small bit of Estonia or Latvia — as it did in eastern Ukraine — what options would then be available? Russia could seek to redress the situation by deploying conventional forces across the border, as in eastern Ukraine, but this would be problematic in the presence of countervailing NATO capabilities in the neighborhood, which should thus help to deter such a salami-slicing ploy in the first place. There were no NATO forces in Ukraine, so all Moscow had to worry about was the dilapidated Ukrainian military. Even there, Russian forces and their separatist allies have been unable to realize anything approaching a decisive victory. Against a more ambitious land grab than the one envisioned by Kofman, the presence of capable NATO forces in the vicinity would be even more useful. Until NATO begins redressing the imbalance of armored forces in the Baltics, such capabilities are conspicuously absent, a fact to which Russian strategists are unlikely to be oblivious.

In the end, our argument does not hinge on believing that only the conventional invasion threat is worth worrying about. We are not tied to a single image of how Russia might seek to undermine NATO, any more than the Kremlin appears committed to a single model of how to employ military power to achieve its ends.

It’s all in the game

Some of Kofman’s statements about RAND’s games reflect incorrect assumptions about what it involved. First, he claims that the Baltic Sea and its coastline was not considered in our wargame and the resulting recommendations. In fact, operations above, on, or under the Baltic Sea figured importantly in every game we ran. Russia’s ability to interfere with NATO’s maritime access to the Baltic Sea using anti-ship missiles based in Kaliningrad consistently loomed large.

Kofman also criticizes the strategies employed by the Russian “red” teams, arguing that they neglected the best Russian approach: to attack through Belarus and seize a land corridor through Lithuania to Kaliningrad, cutting off any NATO forces that might be deployed in the Baltic states. This is certainly a viable concept, and several of our red teams — who were given free play in determining their operational strategy — chose to do something similar in conjunction with their operations further north. This threat is in fact central to our conclusion that a defense strategy based on hurriedly reinforcing the Baltic states after fighting has begun is likely to go badly for NATO.

However, across our games, red players tended to prefer operating further from NATO’s center of gravity in Poland and closer to their own in northwest Russia, typically using Kaliningrad as a firebase for surface-to-air, surface-to-surface, and maritime strike operations. Hitting Russian forces operating in Estonia and Latvia meant NATO air forces typically flew longer missions and were exposed to strong enemy air defenses not just in Kaliningrad, but also in Russia proper. Importantly, by staging out of Russia, red players forced NATO to attack “mainland” Russian territory to get at those defenses and other rear area targets, a choice more fraught with escalatory tension than hitting Belarus.

One can and should debate the merits and drawbacks of various possible adversary strategies. That Russia in fact has more than one option in no way undercuts our finding that NATO’s military posture on its eastern flank is not commensurate with the threat that Russian forces can present there.

In some places Kofman simply misreads the RAND report. He refers to a “10-day invasion rule,” asserting that our scenario allows the Russians “only 10 days’ notice to organize its own invasion.” What we wrote was that NATO had “about a week of warning,” which is quite different from saying that only a week was spent by Russia preparing for its attack.

Kofman misinterprets our observation that when we began the work “there was little to go on in terms of strategic or operational concepts for either side” to mean that the wargames themselves reflected “no operational or strategic concepts.” On the contrary, the whole point of the games was to explore, develop, test, and refine concepts, based on our best — and evolving — understanding of Russian doctrine, tactics, and capabilities, as well as NATO’s extant capabilities and options for enhancing them.

Kofman also takes a passage of our report to unfairly portray us as “Cold Warriors” peddling “outmoded thinking.” Our report states:

A successful defense of the Baltics will call for a degree of air-ground synergy whose intimacy and sophistication recalls the U.S. Army–U.S. Air Force “AirLand Battle” doctrine of the 1980s.

Neither this sentence nor the report as a whole calls for a “replication” or “disinterment” of AirLand Battle. In explaining how the situation “recalls” it, that is, “brings it to mind,” we went on to write:

The games have repeatedly identified the necessity for allied ground forces to maneuver within the envelope of friendly air cover and air support and for ground fires to play an integral role in the suppression campaign against Russia’s advanced surface-to-air defenses. Against an adversary, such as Russia, that poses multidimensional threats, airpower must be employed from the outset of hostilities to enable land operations, and land power must be leveraged to enable airpower.

We are arguing that this is not simply an Army problem or an Air Force problem. It is fundamentally joint challenge and can only be successfully addressed with a degree of cooperation at the institutional and operational levels similar to that which resulted in AirLand Battle.

This invocation of jointness leads us to Kofman’s next misapprehension, which is that the work represents a kind of special pleading for more Army force structure. However, the Baltic games were initiated within RAND to address an internal debate about whether or not the Russians could pose a serious threat to NATO. The effort was only formally sponsored later on by the Army, Air Force and subsequently by the Office of the Secretary of Defense and the Joint Staff. Moreover, the findings of the project do not actually make a case for a larger U.S. Army. In fact, the prescription for deploying forces to northeastern Europe is explicitly about where existing forces are based and how ready they are to fight on short notice, not about the overall size of the Army. Russia could attack with relatively little warning and achieve operational victory in a matter of days in the absence of serious resistance on the ground, rendering irrelevant heavy NATO forces that require weeks or months to mobilize and deploy from North America or western Europe. Instead, bolstering deterrence in this scenario calls for a well-armed ground force of relatively modest size but high readiness, postured in or near the Baltic states.

Finally, it is important to clarify that the games were not mere BOGSATs (Bunch Of Gurus Sitting Around Talking). Every iteration of RAND’s “table top map with blue and red unit counters,” as Kofman puts it, was run by an adjudication cell made up of experts in air, land, and maritime operations, most of whom have two or three decades of professional experience analyzing combat outcomes. These analysts provided quantitative assessments of air, land, maritime, space, and cyber activities to both the blue and red teams based on rules and statistical combat results tables derived from extensive combat modeling.

Seen from a distance, such an approach to military analysis can appear simplistic, especially to those who equate rigor in wargaming with the use of heavily automated and largely opaque processes for adjudication. However, our experience has shown that expert-adjudicated games using transparent and adaptable processes can reveal much more, and their results are less susceptible to misrepresentation. This is especially true when, as in this case, the games are repeated extensively with a variety of players and the effort integrated with other analytical approaches.

What these games make clear is that the forces currently postured to defend the Baltic states are insufficient to prevent an invading army (which Kofman calls undersized) from overrunning large portions of two or three alliance member states in short order. The problem is not that the Russian army is huge (it is now a small fraction of the size of the Soviet army during the Cold War) but that it arrives quickly on an expansive and mostly empty battlefield. Together, the Baltic states are about the size of the Federal Republic of Germany prior to unification, but have only 10 percent as large a population. NATO can bring a lot of airpower to the fight rapidly. But with only light infantry units and a scattering of light armor to stand in the way of the Russian advance, there is little opportunity for air attacks to inflict much cumulative damage on the invaders before they reach the Baltic capitals or other objectives. Further, Russia’s extensive surface-to-air defenses both complicate and limit NATO’s ability to bring its airpower to bear on the invading force.

U.S. and allied ground reinforcements would not only take too long to arrive, but would also face great difficulty reaching the Baltic states at all from Russian missile threats against incoming ships or aircraft and long-range rockets from Kaliningrad and Belarus that dominate the only overland access, a narrow corridor from Poland.

Making Deterrence Robust

It is important to recognize that fighting a war with Russia in northeastern Europe would be a strategic failure, potentially one with catastrophic costs, whether NATO wins or loses. Deterring such a conflict is of paramount importance.

Ideally, deterrence should be both strong and robust. Deterrence is strong when going to war appears much worse to a prospective attacker than not doing so. However, deterrence can be strong yet fragile if its strength depends upon particular conditions that could change or upon unsound assumptions. Deterrence is robust when aggression will still look like a very bad idea even in the event of unexpected but plausible shifts in the strategic situation or the opponent’s beliefs. A deterrence strategy that falls apart in the event of being abandoned by an unreliable protector (consider the Molotov-Ribbentrop Pact) or the enemy concocting a clever scheme that promises to make an affordable or decisive victory possible where it did not appear to be before (think Yamamoto’s plan to attack Pearl Harbor) lacks robustness. Put another way, the deterrence strategist should seek not only to make war look unappealing to the opponent, but also to make it as difficult as possible for a cunning enemy planner to create a compelling presentation describing to his superiors how it might be possible to start a war and not be unhappy with the result.

The principal merit of stationing NATO forces that could mount a serious defense against a Russian invasion in or near the Baltic states is that doing so offers a degree of robustness in deterring attack that the principal alternatives do not appear to provide. If invading the Baltic states appears certain to lead to a sustained and costly fight against substantial American forces deployed in the territories in question, it should be very hard to spin even a best-case scenario in which the game would appear to be worth the candle.

In contrast, deterrent approaches that depend upon threatening to punish Russia for occupying the Baltic states after the fact, as Kofman prefers, would be susceptible to Russian leaders imagining — rightly or wrongly — that these threats would not actually be carried out. Similarly, a threat by the Baltic states to wage prolonged partisan warfare against an occupying force might well lack credibility given the potential costs to the populace of doing so, especially against an occupier as ruthless as the one that razed Grozny. Leaving the Baltic states to fend for themselves in the event of an invasion would also represent a catastrophic failure by NATO to honor its Article 5 responsibilities.

A NATO strategy based on temporarily accepting the inevitability of an invasion succeeding and instead mobilizing an overwhelming force to counterattack against Russian forces and liberate the Baltic states might encounter similar skepticism in the Kremlin. It would depend on the alliance remaining determined to right the wrong through costly military action even after months of Russian reinforcement, propaganda, and subversion. Moreover, Moscow might well persuade itself that threats to use nuclear weapons in defense of Kaliningrad (which would stand in the way of a counteroffensive as a “nuclear landmine” in Kofman’s incisive turn of phrase) and its newly acquired territory in the Baltics would be sufficient to deter NATO from carrying through with a “we shall return” promise. Indeed, such an expectation could prove to be correct.

The presence of small U.S. military contingents in the Baltic states to serve as a tripwire is often proffered as a solution to the credibility issues that many of these approaches could face. According to this argument, Russian leaders would recognize that killing even a handful of American troops in the course of an invasion would commit the United States to fight until it achieved victory. Thus, stationing brigades in the Baltic states would offer little additional value over having, say, rotational deployments of token companies there. This does not appear to be the only way that Russian strategists might look at the problem, however. Small units might instead appear to be useful hostages for the invaders to use as a tool for undermining Washington’s determination to keep fighting.

Each of these less-direct deterrent approaches might contribute usefully to discouraging Russia from attacking the Baltic states. However, none appears to offer the degree of robustness that could be expected from forward deploying heavy ground forces where they could stand in the way of an invasion, allowing NATO airpower to come more fully into play and making it clear even to an excessively optimistic Russian planner that the Baltic states could not be overrun quickly and inexpensively. Much analysis remains to be done on matters such as comparing various deployment and prepositioning options and to consider how such forces might best be configured to maximize their defensive capabilities without unnecessarily provoking Russian anxieties about potentially offensive threats on their borders. Wargames promise to continue being useful for shedding light on these and other issues related to strengthening deterrence in the Baltic region.

Karl Mueller is a senior political scientist, David Shlapak is a senior international research analyst, Michael Johnson is a senior analyst and David Ochmanek is a senior defense analyst at the nonprofit, nonpartisan RAND Corporation.

Image: U.S. Army Sgt. James Avery