Lithuania – the mouse that roars

Russia could well test NATO by attacking Lithuania, but Vilnius is better prepared than most. A Lithuanian state border guard stands on patrol near Belarus on June 21, 2021 near Poskonys, Lithuania. Belarus has weaponized migration flows by illegally allowing refugees to pass through its borders and into the Schengen Area. In a nutshell Lithuania is one of NATO’s most exposed frontline states Kaliningrad and Belarus create serious escalation risks in border areas Vilnius has shown how national resolve can strengthen allied deterrence. As worries mount over possible Russian aggression against NATO, the central question is where Moscow would be most likely to attack first. Provocations on the southern flank cannot be ruled out. A move against, say, Romania could form part of a larger plan to destabilize Moldova. But the most likely targets are the three Baltic states, which are currently subjected to a variety of Russian hybrid operations. Short of a full-scale attack on all three Baltic states, which would trigger a forceful NATO response, the most likely scenario is a probing strike against one of them, designed to test the alliance’s reaction. To the north, Estonia has ample reason to be concerned. Its sizable Russian-speaking minority has long been targeted by Kremlin propaganda, which seeks to turn it into a potential Trojan horse. The country’s easternmost city, Narva, which borders Russia, is almost completely Russian-speaking. In war games exploring a possible Russian attack, Narva has often featured as a likely target. Moscow’s propaganda also openly discusses using the alleged need to protect Russian speakers as a pretext for invasion, much as it did in Ukraine’s Donbas region. A target for the Kremlin Although the threat to Estonia is real, aggression against Lithuania is both more likely and more challenging. An important reason is the Kaliningrad exclave, a part of the Russian Federation that is locked in between Lithuania and Poland. In Russian war planning, it has played a crucial role, both as a lock on the southern Baltic and as a base to project force against Poland and Germany. The war in Ukraine, however, has drained much of its military strength and turned it into a major vulnerability. This weakness may paradoxically heighten the danger to Lithuania. Although Kaliningrad’s borders with Poland and Lithuania have not been fully closed, the Russian full-scale invasion of Ukraine has severely restricted cross-border movement. The exclave is presently in a critical situation. Supplies may be brought in by sea, but the real lifeline is rail transit from Belarus via Lithuania. The corridor arrangement was negotiated in the 1990s, after Russia demanded a dedicated military transit route. Lithuania refused, arguing that such a corridor would compromise its sovereignty, but European pressure ultimately pushed it to permit transit under Lithuanian control. Since the war on Ukraine, Vilnius has expressed concern about threats to its own security, but Brussels has remained adamant that the route must be kept open. The Suwalki Gap The Suwalki Gap is the narrow land corridor between Poland and Lithuania that separates Kaliningrad from Belarus. It has long been viewed as a NATO vulnerability on the alliance’s eastern flank. In early 2026, a Lithuanian war game was held to simulate infiltration by Russian operatives arriving by train. What makes the transit issue so thorny is that while Lithuania fears it may be used as a prelude to an invasion, Russia fears that a complete halt to all traffic would make the situation inside Kaliningrad extremely difficult. The total lack of confidence between the two sides enhances the risk of escalation. Another reason for Lithuanian concern is linked to its long border with Belarus. In power since 1994, Belarusian President Alexander Lukashenka has proven to be the ultimate survivor. Before Russia’s war against Ukraine, he played a finely tuned game of alternately leaning toward the Kremlin and toward Europe. Since the war began, he has been pulled into Moscow’s camp and now serves as an increasingly important proxy for Russian operations. As Lithuania emerged as a leading voice in European support of Ukraine, its relations with Belarus deteriorated sharply. Incidents have ranged from weaponizing migrants that are pushed to cross the border to balloons allegedly smuggling cigarettes that have repeatedly disrupted air traffic. The primary vulnerability to a Russian attack lies in the Suwalki Gap, a 65-kilometer stretch of land border between Poland and Lithuania that separates Kaliningrad from Belarus. Before the accession of Sweden and Finland to NATO, there was concern that by closing this gap Russia could isolate the three Baltic states from continental NATO. Preparations to counter such a scenario ranged from inserting troops by helicopter to conducting guerrilla operations behind Russian lines. With Sweden and Finland in NATO, this threat has lost its previous strategic urgency, but the danger of a Russian attack is still taken very seriously. An important reason is that the American commitment to defend all NATO members is being questioned. The Lithuanian example On their side of the border, Polish forces have made ample preparations to counter an attack. They are supported by a contingent of just over 1,000 U.S. troops, based at Bemowo Piskie. On the Lithuanian side, local forces are in a similar state of enhanced readiness, supported by a German heavy mechanized brigade, based in Rukla. While President Trump’s unpredictability casts a shadow over the future role of U.S. troops in Europe, Germany’s commitment is strong. Launched in May 2025, as part of the 10th Panzer Division, the 45th Panzer Brigade was created to meet Lithuanian demands for a permanent German presence. Colloquially known in Germany as the Litauenbrigade, it will, once fully staffed, number 4,800 troops and 200 civilians and be equipped with main battle tanks and infantry fighting vehicles. Foreign military support matters, but Ukraine’s most important lesson is that such support becomes decisive only when a country first demonstrates its own resolve to defend itself. Without the determination of the Ukrainian government and the widespread backing of its population, outside assistance would not have been enough to withstand Russia’s invasion. This is where Lithuania stands out, setting an example in both resisting Russian pressure and supporting Ukraine. There are strong historical reasons for Lithuania’s fierce commitment to defending its independence. The country has long seen itself as standing at the center of Europe, with a national memory rooted in the geopolitical importance of the old Grand Duchy of Lithuania. Even before its later union with Poland, Lithuania had absorbed much of the former Kyivan Rus and pushed north against Muscovy, creating a realm that stretched from the Gulf of Finland to the Black Sea. After its union with Poland, formalized in 1569, it stood at the forefront of centuries of confrontation between Muscovy and Europe. During the Cold War, much of this was forgotten. European security revolved around NATO and its members in Western Europe. That is now being radically altered. As the center of gravity in European security shifts decisively eastward, Lithuania is once again central to events, and its resilience in the face of Russian pressure is being tested. A leading voice in meeting this challenge was Gabrielius Landsbergis, Lithuania’s foreign minister from 2020 to 2024. Born under Soviet occupation, he had seen his grandfather, Vytautas Landsbergis, a music professor, lead Lithuania’s struggle for independence from Soviet rule before becoming one of the country’s defining post-Soviet political figures. During his own time in office, Gabrielius Landsbergis ensured that Lithuania punched well above its weight, taking a hard line on sanctions and often chastising other Europeans for appeasing Moscow. Even after leaving office, his influence has endured. Lithuania has also remained at the forefront of the coalition of European states unwilling to yield to Russian aggression. The key question is how far the rest of Europe is prepared to go in supporting Lithuania and other frontline NATO member states. Scenarios Most likely: Deterrence holds The most likely scenario is that deterrence will be sufficiently credible to discourage Russian aggression. Over and above the resolve shown by the Lithuanians themselves, Germany has finally taken a firm stand after years of prevarication about its role in defending Lithuania. The creation of the 45th Panzer Brigade will have a consequential impact. The German commitment was symbolized in a public inauguration ceremony on Cathedral Square in Vilnius. In attendance at the military parade were German Chancellor Friedrich Merz and Minister of Defense Boris Pistorius, together with their Lithuanian counterparts, President Gitanas Nauseda and Minister of Defense Dovile Sakaliene. Deterrence is further strengthened by the commitment of Lithuania’s partners in the Nordic-Baltic Eight, who increasingly view Lithuania’s defense as part of their own. Russian planners must also expect that an attack would be sure to result in Poland joining the fight and in Ukraine providing expert assistance in drone warfare. Less likely: Deterrence fails and Russia attacks The abovementioned scenario presumes rationality on the Russian side, weighing the costs of aggression against the expected benefit. A scenario where deterrence fails and Moscow attacks could materialize because of sheer desperation in a last-ditch attempt to push back against NATO. It could begin with Russian special forces entering Lithuania aboard the Kaliningrad transit train, followed by Russian forces pushing out from Kaliningrad. Two factors suggest that if such a scenario unfolds, it would likely happen fairly soon. The first is that the correlation of forces is moving decisively against the Kremlin. As Russia’s armed forces are drained by the war in Ukraine and demoralized by territorial losses, some of NATO’s “willing” members are taking major steps to strengthen their own military capabilities and deepen cooperation with Ukraine. The other concerns recent actions and statements by the Trump administration and Hungary’s Viktor Orban, which Polish Prime Minister Donald Tusk has said “all looks like Putin’s dream plan.” While the Russian regime is encouraged by these actions, it must also be aware that the window is closing, that U.S. support for Moscow is about to reach its peak and that a new leadership in Washington may take a very different stance. It cannot be ruled out that the Kremlin will opt for a final act of defiance, hoping that NATO will fracture and abandon Lithuania.