NATO seems more united today than it has been at any time since the end of the Cold War. An aggressive Russia, unbowed by Western economic sanctions after its annexation of Crimea and intervention in eastern Ukraine, has driven NATO member countries closer together. However, if given the opportunity, an aggressive Russia could also put NATO in a position that could strain its cohesion and ultimately undermine its existence. One place where that could happen is in the Baltics states of Estonia, Lithuania, and Latvia.
Bigger, Not Necessarily Stronger
As part of NATO’s eastward expansion after the Cold War, the Baltic countries joined the Alliance in 2004. But geographically separated from nearly all of NATO and having small militaries, the Baltics have always been vulnerable. From the start, military planners understood that NATO would have to commit substantial resources to properly defend the region from a Russian invasion.
At the time, NATO’s European governments were unconcerned. Russia, they believed, no longer posed a real threat. So, rather than make the costly outlays needed to protect the Baltic states, they cut their defense budgets. It was little surprise, then, that Europe’s conventional military forces saw their numbers and combat readiness fall. Today, France, Germany, and the United Kingdom would each be hard pressed to rapidly deploy a single combat-ready armored brigade. NATO’s reduced fighting capacity was also evident in its air campaign over Libya in 2011. After less than a month of combat, European air forces ran short of precision-guided munitions.
Moreover, given how easily Russia could sever the land and air routes into the Baltics, one might have expected NATO to have boosted its amphibious capacity in case it needed to send reinforcements across the Baltic Sea. Instead, NATO’s combined sealift capacity, excluding U.S. amphibious forces, has fallen to such a low level that it can ferry little more than two infantry brigades. Even worse, almost all of that capacity is based far from the Baltic Sea. And even if NATO could transport those brigades to the Baltics (through what might be a gauntlet of Russian air and missile strikes from Kaliningrad) it is doubtful whether they would be enough to stop a mechanized Russian invasion.
Peril of the Interregnum
Should NATO prove too unprepared to help the Baltics, Russia could achieve a quick victory. That would mean that NATO would have to mount a counteroffensive to liberate the region in order to fulfill its treaty obligations. But before it could do so, the Alliance would need time to fully mobilize its armed forces. During that interregnum, between Russia’s victory and NATO’s counteroffensive, NATO leaders would have time to contemplate what was to come.
They would have a lot to consider. Since the only land route into the Baltics runs through the 100-km wide Suwalki Gap, a narrow corridor between Lithuania and Poland, NATO ground forces would have little choice but to mount a frontal attack. Massed Russian artillery could turn the gap into a killing zone. Meanwhile, Russia’s coastal defense batteries and attack helicopter battalions could inflict heavy losses on any amphibious assault.
The conflict could also escalate beyond the Baltics. As a prelude to any counteroffensive, NATO commanders would naturally want to use their air power to attrit Russian forces and logistical capacity as well as suppress Russia’s supporting artillery, air defense, and coastal defense batteries. That would require strikes against targets on not only Baltic soil, but also possibly Russian soil. Moscow could seek reciprocity. It could launch air or missile strikes on similar targets in Western Europe and the United States. Russia could even escalate to a nuclear confrontation. In effect, it could thrust upon NATO leaders the decision: “Is Tallinn worth Berlin?”
Ultimately, the near certainty of high casualties, the uncertainty of battlefield success, and the possibility of a wider war might cause NATO leaders to think twice about liberating the Baltics. Russian information operations would likely exacerbate those concerns to sow doubt and division within NATO countries. If NATO leaders were to hesitate during the interregnum and agree to a settlement that left any part of the Baltics in Russian hands, then no NATO member could fully trust NATO’s security guarantee again. The rationale for NATO would be lost and its future existence put at risk.
The Tripwire Fix
NATO faced a similar danger during the Cold War. At that time, the Soviet Union and its Warsaw Pact allies had amassed such enormous conventional forces that they threatened to overwhelm those of the Alliance. Observers wondered whether the United States would risk a nuclear confrontation with the Soviet Union if it quickly occupied Western Europe. The question put to American leaders was: “Is Bonn worth Washington?” NATO responded by stationing large U.S. military forces close to the frontline, in part, to act as a tripwire. They would incur the first casualties of any Soviet invasion. Those losses would bind the United States and its nuclear arsenal to the defense of Western Europe, and thus deter the Soviet Union from invading it in the first place.
NATO appears to be trying a similar tactic in the Baltics states. For years, NATO has rotated tiny military contingents through the region. But over the last year, their sizes have grown. Currently, a German-led battle group of 1,000 soldiers is in Lithuania. Later this year, a Canadian-led battle group will be in Latvia and a British-led one will visit Estonia. Though still too small to stop a Russian invasion, they could serve as a tripwire to bind the rest of Europe to the defense of the Baltics. However, that only works if NATO can prevent Russia from achieving a quick victory, since the prospect of a costly counteroffensive could still render NATO’s tripwire ineffective.
To reliably avoid Russia’s existential threat, NATO must ensure that Russia is unable to score a quick victory in the Baltics. That requires NATO members to pledge more than words of resolve. That requires more resources for more troops, better equipment, and, above all, higher combat readiness.
Most exposed to the Russian threat, NATO’s Eastern European members are leading the way. Poland created a new Territorial Defense Force of reservists who will number 53,000 in two years. It also ordered 128 upgraded Leopard 2PL main battle tanks. All three Baltic countries have acquired new light armored vehicles. Better yet, they are beginning to acquire the firepower needed to slow a Russian advance. Lithuania recently bought PzH2000 self-propelled howitzers, and Estonia is in discussions to purchase K9 long-range artillery.
The rest of NATO needs to do the same. After all, one of the key reasons why NATO was so important in the most successful unfought war of the last century, the Cold War, was because its member countries were conscious to brook no ambiguity about the Alliance’s combat readiness to take on its main adversary.
 Remigiusz Wilk, “Polish Territorial Defence Force expanded to 53,000 personnel,” Jane’s Defence Weekly, Nov. 17, 2016; Remigiusz Wilk, “Poland orders 128 upgraded Leopard 2PL main battle tanks,” Jane’s Defence Weekly, Jan. 4, 2016.
 Nicholas de Larrinaga, “Estonia begins K9 artillery negotiations with South Korea,” Jane’s Defence Weekly, Feb. 7, 2017; Nicholas de Larrinaga, “Lithuania receives first PzH 2000 howitzers,” Jane’s Defence Weekly, Jun. 28, 2016.