Abstract: The 2014 and 2022 invasions of Ukraine by Russia have forced many European nations, especially the Baltic nations of Latvia, Lithuania, and Estonia, to reconsider their military defences, grey zone security measures, and civil preparedness in response to wide-ranging Russian threats. The Baltic nations have increased defence spending and capabilities, worked in the grey zone between combat and peace to address hybrid threats, and prepared their civilian population for large-scale conflict.
Problem statement: How are the Baltic nations adapting their defence strategies to deter Russian aggression amid uncertainty over long-term American commitment to Europe?
So what?: Other European nations, especially those close to Russia, should look at how the Baltic nations are addressing these threats and take similar actions to deter conflict. Russia has signalled that its ambitions lie far beyond Ukraine.
Background and Threat
Since the 2014 invasion of Ukraine, Russian aggression has been aimed at NATO’s easternmost flank. Geographically located near Russia and Belarus, the Baltic nations of Estonia, Latvia, and Lithuania have historically been culturally, economically, militarily, and diplomatically linked to Russia. However, since the demise of the Soviet Union in 1991, these former Warsaw Pact nations have shifted their relations westward, joining organisations such as the EU and NATO to strengthen their economies and security. A revisionist Russia under Vladimir Putin is seeking to restore its Cold War levels of influence in Europe by pulling the Baltic nations away from the West and back into Russia’s sphere of influence. Currently, the Baltic nations are at the forefront of aggressive rhetoric and grey-zone attacks from Russia. This forces a repositioning of their defensive, security, and civil preparedness structures to respond with force should the need arise, deter grey-zone attacks, and build societal resilience. To do so, this multilayered strategy relies on fortifications. Secondly, increased security measures are being implemented to address grey-zone attacks, including cyber and information campaigns, GPS jamming, and sabotage. Finally, civilian preparedness measures are being organised, such as the expansion of territorial defence units and the implementation of evacuation routes and bomb shelters.
In the aftermath of the breakup of the Soviet Union, many in the former Warsaw Pact nations sought to grow their economies in ways prohibited under communist rule. After 1991, the economies of these nations declined as they transitioned from central planning to free market economics. Inflation in the Baltic nations peaked at about 1,000% in 1992, then began to recover shortly afterwards, rising again in 1998 due to lingering ties with Russia, which was experiencing its own economic challenges at the time.[1] However, the transition to a free market stabilised their economies, and growth accelerated in the following years. This resulted in an expansion of individual incomes and GDP, which, in turn, increased standards of living, global interconnectivity, and international trade. While initially lagging far behind Western European nations, Estonia, Latvia, and Lithuania would see immense economic growth and stability. This was in large part due to an embrace of technology and digitalisation, which led to their inclusion in the European Union in 2004.[2] A few months after joining the EU, the Baltic nations would also join NATO, signalling deeper ties to the Western world to address needs that were not strictly economic.[3] This would send a strong message to Russia, as the former Warsaw Pact nations, Poland, the Czech Republic, and Hungary, had also joined NATO prior to the inclusion of the Baltic nations.
Noticing this was Putin, the former KGB operative and long-ruling leader of Russia. Putin harboured a revisionist ideology of Russia, in which Russia’s former influence over Eastern Europe would be reestablished to provide Russia the prestige and security it once enjoyed during the Cold War. To do so, Russia would engage in war in Georgia and Ukraine, as it justified its land grabs in each country by claiming to be protecting Russian-speaking ethnic groups found in each nation from their own governments. Similar rhetoric was directed toward other European nations, with the most alarming coming from a Telegram channel advocating a “Narva People’s Republic” composed of Russian speakers in Estonia in 2006.[4] While this could be excused as a nominal threat, Russian State Duma Chairperson Vyacheslav Volodin also claimed that the Latvian government is “persecuting” Russian speakers in 2025.[5] This matches messaging that came before the Russian invasions of Georgia and Ukraine. Since Putin sees himself as the protector of Russian-speaking peoples in former Warsaw Pact nations, the Baltic nations have good reason to see themselves as next in line for an invasion.
Conventional Deterrence
To address these issues, the nations of Estonia, Latvia, and Lithuania have begun reallocating resources and attention in ways that have adequately responded to these threats. To address conventional threats, defence spending has increased, NATO ties have been tightened, and military fortifications have been constructed. The fighting in Ukraine has proven that a large-scale conventional war in Europe is possible, and Putin’s threats demonstrate his ambitions lie far beyond Ukrainian territory.
To deter or fight Russian conventional forces, the Baltic nations have increased their defence spending. Latvian defence spending is at 4.91% of its GDP.[6] Lithuania is currently spending 5.38%, almost three times its 2019 expenditure percentage.[7] Estonia’s 2026 defence budget is 5.4% of its GDP, with massive increases in defence investment and operating costs compared to past years.[8] Each of the Baltic nations has pledged not only to increase its spending but also to maintain high levels of spending to better procure weapons, build and maintain stockpiles, invest in new technologies, and expand the size of their militaries. Anti-tank munitions, long-range artillery, air defence systems, and counter-drone technology procurement are all derived from lessons learned in Ukraine.
To better deter any Russian aggression, NATO nations, especially the Baltic nations, have tailored their military exercises to prepare for any real-world threats. Spring Storm, a NATO exercise held in Estonia and Latvia, involved 12,000 NATO troops and focused on defensive operations in conventional combat.[9] These troops practised rapid deployment across Europe to the simulated front lines in the Baltics. Another exercise, Sabre Strike 26, also took place and, like the previous one, focused on deploying troops to NATO’s easternmost borders, from Poland to Finland.[10] Troop movements were very well publicised, not only to make civilians aware of road closures but to signal to Russia that NATO was prepared and willing to deter or fight a war should the need arise. Above the tactical level, integration was a focal point at the battalion and brigade levels, so mixed units could be prepared to fight as a cohesive alliance. An emphasis on defensive warfare was publicised to calm any tensions that arise whenever NATO conducts large-scale exercises this close to the Russian border, striking a good balance by deterring invasion while avoiding escalation.
As NATO is a defensive alliance, the Baltic nations have also increased not only their spending and NATO cohesion, but also their defensive fortifications. Known as the Baltic Defensive Line, Latvia, Lithuania, and Estonia are constructing hundreds of bunkers, miles of trenches, supply depots, anti-tank ditches, fences, and static obstacles. This is done to prevent a Russian ground invasion, deny potential enemies’ room to manoeuvre, and buy time for reinforcements to arrive to defend all of their territory.[11] While the Baltic nations can do little to overcome Russia’s immense numerical advantage, they can use these fortifications to buy time for reinforcements to arrive from deeper within Europe. Following a deterrence-by-denial strategy rather than a deterrence-by-punishment strategy, the Baltics aim to make a Russian invasion unlikely to achieve its objectives and thus unlikely to be considered. This posture also reassures Russia by positioning the Baltic nations in a way that makes a counterattack unlikely, avoiding an unintended provocation that would require a more offensive posture.[12] Ukraine has shown that static defences can be held in 21st-century combat, and the Baltic nations have seemingly taken notice.
Grey Zone Defence
In recent years, Russia has conducted numerous multi-domain grey zone attacks against Baltic nations and other NATO nations in the region. These attacks seek to probe defences, undermine the belief that Baltic governments can defend their territory, communicate Russian intent, and undermine NATO cohesion. These attacks include cyberattacks against government and military networks, information operations targeting civilian perceptions, GPS jamming against shipping and aviation, and sabotage operations. All of these operations provide Russia with some degree of deniability because of the unclear ties to the Russian government, making it difficult for the Baltic nations to respond. Acts like these also allow Russia to maintain a low level of offensive capabilities, gradually draining resources and drawing attention. However, these nations have made efforts to respond publicly as well as behind the scenes. Hardening cyber infrastructure to prevent and deter future attacks, and improving civilian resistance to disinformation and misinformation operations, seek to mitigate the effects of cyber and information operations. Efforts to track, identify, and mitigate GPS jamming are underway. Finally, more active protective measures to prevent sabotage of strategic infrastructure are also being enacted. The Baltic nations are frequent targets of these grey-zone attacks, and their new strategic posture extends beyond military defences.
In 2023, a NATO summit in Vilnius faced numerous cyberattacks, ranging from the shutdown of affiliated websites to massive disinformation campaigns, disrupting meetings and events.[13] The year prior, Lithuania’s state-owned energy conglomerate was on the receiving end of a massive cyber-attack, during which sensitive data was stolen, likely in response to sanctions against Russian energy exports.[14] Information operations in support of Russia are also commonplace, with coordinated online efforts made to undermine support for Ukraine, NATO, and Baltic democracy, and to inflame social divisions specifically among Russian speakers and Baltic youth.[15] In response, the Baltic nations have begun to work more closely with civilian cyber defence companies to identify, track, and respond to cyber-attacks. The NATO Cooperative Cyber Defence Centre of Excellence, located in Estonia, provides research, training, and exercises for NATO cyber defence.[16] This centre was founded in 2007 after a Russian cyber-attack against Estonia after Tallinn’s removal of a Soviet era statue from a graveyard. It has seen a recent expansion, with Ukraine joining as a non-NATO participant in 2021 to share and receive lessons learned from its war against Russia.[17] More recently, the EU-NATO Task Force on the resilience of critical infrastructure was established in 2023 to protect civil infrastructure and economic services against cyber threats.[18] Cyber threats are not only government-sponsored, but can be attributed to non-state actors, making this a grey zone threat that is being exploited by Russia.
GPS jamming, spoofing, and interference have also become more common against the Baltic nations. While some of these acts are legitimate acts of war against Ukraine, an uptick in disruptions against commercial shipping lanes, aviation, and GPS devices may be indicative of Russian grey zone operations. Estonia and Lithuania have both accused Russia of interfering with GPS receivers on planes attempting to land at airports, creating significant safety risks to passengers and crew.[19] This could be Russia seeking to increase worry in the Baltics, unintended cascading effects from its war against Ukraine, or attempts to probe the defences of civilian GPS uses. As a result, the Baltic nations have cautioned maritime vessel operators against relying solely on GPS for navigation and are working to locate jamming emitters to identify perpetrators. Talk of tougher enforcement of international water and airway norms and laws is underway, but a lack of definite attribution likely means these attacks will continue. Therefore, mitigating procedures such as area avoidance and reliance on radar navigation are likely to yield the best possible outcome.
Finally, acts of sabotage have been attributed to Russia as part of Moscow’s efforts to undermine security through grey zone attacks. Since 2022, there have been more than eight undersea sabotage operations in the Baltic Sea.[20] These attacks can be as simple as dragging a ship’s anchor for miles, destroying undersea cables that carry telecommunications messages and other forms of data. The UK claims that Russian military submarines have conducted reconnaissance in order to identify the locations of these cables for future operations.[21] In 2024, Estonian security services detained 13 people for vandalising national monuments and the personal vehicles of ministers and journalists.[22] Around this time, two individuals attempted to set fire to a museum in Latvia and an Ikea store in Lithuania.[23] While these were mostly amateurs recruited through Telegram and conducting low-cost, low-threat missions, the main threat lies in their ability to cause greater damage or even death if these attacks are scaled up. In response, the Baltic nations increased cooperation with regional and international law enforcement, better monitored social media and messaging apps, and tightened border security. There have also been more overt responses, with increased naval patrols around undersea cables and the boarding of vessels suspected of having taken part in sabotage operations.
Civil Preparedness
To better prepare their civilian populations for war, the Baltic nations have created a civil preparedness training program and outlined evacuation routes and shelters. This is designed to build confidence in their government’s ability to respond and protect civilian lives in the event of war, as well as to build societal resilience. To build this resilience, Estonia has the Defence League, Lithuania has the Riflemen’s Union, and Latvia has the National Guard. These units, which have existed for years, bridge the gap between military and civilian roles in society, preparing for a flexible response to small military incursions or large-scale combat, as seen in recent events in Ukraine. Conscription is also mandatory in all three nations, but participation in these units is voluntary, ensuring a continuation of military skills throughout society and a dormant knowledge set for all males who are able to serve. For those not expected to partake in combat, evacuation routes are set up to move large numbers of citizens from densely populated cities to safe areas in the region. Bomb shelters have also been constructed and can house between 17% and 140% of the Baltic populations, depending on location.[24]
The role the civilian population plays in defence is vital for Baltic preparations against Russian aggression. Estonia has what is known as the Defence League. Joining and leaving are optional for those over 18, with youth participation available as well.[25] Mostly working near the border, the Defence League also has a cyber component and fulfils other defence tasks, such as guarding vital infrastructure within its locality. Similarly, Lithuania has the Rifleman’s Union, which addresses disaster relief and combat operations during war and offers military educational services for those under 18.[26] Able to integrate into the military during times of war, it has seen thousands of new members join since 2022. Latvia’s National Guard has units that rotate through heightened states of readiness, able to support disaster relief efforts in peacetime or conduct combat operations when at war.[27] Politicians are seeking to expand the National Guard soon, but no timeline or specific details have been announced. The roles these voluntary, part-time organisations play are vital to increasing knowledge of defence capabilities. This builds a society resilient to aggression and increases the number of service members who can be called upon to respond quickly to situations with high degrees of flexibility at a lower operational cost than a full-time military unit.
Finally, civil preparations have also included evacuation routes and bomb shelters. Evacuation routes from major population centres to safer rearward locations have been established and can be traversed by large percentages of the population should the need arise. Mass casualty drills involving civil service organisations have taken place, and procedures have been established to streamline strategic communications to civilian populations. Many public spaces have been retrofitted to act as bomb shelters, including schools, churches, community centres, and other public buildings. The Swedish Ministry of Defence released a memorandum of understanding concerning the cross-border movement of civilian populations in the Baltic and Nordic regions. This included measures for border control, reception and registration, and the establishment of evacuation corridors.[28] Lessons learned from the early days of the Russian invasion of Ukraine in 2022 played a large role in shaping these plans. This commitment of resources and time by regional governments underscores the seriousness of the changing status quo in Eastern Europe.
Conclusion
The Russian invasions of Ukraine in 2014 and 2022 forced European governments to recognise once again that large-scale conventional war remains possible on the continent. In response, the Baltic nations of Estonia, Latvia, and Lithuania have adopted a multilayered defensive strategy designed not only to deter a conventional invasion but also to withstand grey-zone coercion and strengthen societal resilience. Rather than relying solely on military modernisation, the Baltic approach integrates conventional deterrence, hybrid defence measures, and civilian preparedness into a broader national security framework.
This strategy reflects the unique strategic realities facing the Baltic states. Geographically exposed and unable to match Russia in manpower or conventional military mass, the Baltics have prioritised deterrence-by-denial. Fortifications, territorial defence units, expanded military spending, and closer NATO integration are intended to complicate any potential Russian offensive long enough for allied reinforcements to arrive. At the same time, investments in cyber defence, infrastructure protection, civil preparedness, and public resilience seek to reduce the effectiveness of Russian grey-zone tactics aimed at destabilising societies without triggering open war.
The Baltic response also demonstrates how smaller states can adapt to an increasingly uncertain security environment. Concerns regarding the long-term reliability and speed of external assistance have encouraged European nations, particularly those closest to Russia, to assume greater responsibility for their own defence. Poland, Finland, Sweden, and the Baltic states have all expanded defence spending and preparedness measures, recognising that deterrence requires both military capability and societal cohesion.
At the same time, the effectiveness of this strategy will ultimately depend upon NATO unity and the credibility of collective defence. The Baltic nations can impose significant costs on a potential aggressor and delay military advances, but they cannot independently sustain a prolonged conventional conflict against Russia. Their strategy, therefore, rests upon the assumption that NATO reinforcement would arrive rapidly and cohesively during a crisis. Continued multinational exercises, interoperability, and forward defence planning remain essential to maintaining that credibility.
While this multilayered defence provides immense benefits for the Baltic nations, it does have its drawbacks. There is nothing these nations can do to dramatically increase their population sizes. Their small territories also leave them vulnerable to a quick and decisive defeat before NATO can be fully mobilised. Uncertainty regarding future American engagement also threatens the security of not just the Baltics but all of Europe. Finally, the grey zone measures taken against those in the region leave them vulnerable to a long-term, but low-intensity threat level. Russia can scale the level of aggression up or down, creating the risk of rapid, unintended escalation as well as new challenges in the future that will demand reposturing.
The Baltic model offers important lessons for other NATO members confronting revisionist and hybrid threats. By combining conventional military preparedness with cyber resilience, territorial defence, and civil mobilisation, the Baltic states have developed a comprehensive deterrence approach suited to modern conflict. While no strategy can eliminate the risk of escalation or miscalculation, the Baltic approach demonstrates how smaller nations can strengthen national resilience and raise the costs of aggression in an increasingly unstable European security environment.
[1] The Borgen Project, “How the Baltic States’ Economies Exploded Post-U.S.S.R.,” BORGEN Magazine, November 15, 2022, https://www.borgenmagazine.com/baltic-states-economies/.
[2] Baltic Assembly, “Integration,” accessed May 19, 2026, https://baltasam.org/history/integration.
[3] “From Impossibility to Reality: Baltic States’ Journey to NATO, 1997–2004,” Centre for Geopolitics, November 3, 2024, https://www.cfg.cam.ac.uk/news/from-impossibility-to-reality-baltic-states-journey-to-nato-1997-2004/.
[4] Meelis Oidsalu, “A New Russian Game on the Borders of the Baltics,” CEPA, March 19, 2026, https://cepa.org/article/a-new-russian-game-on-the-borders-of-the-baltics/.
[5] Stefaniia Bern, “Russian Offensive Campaign Assessment, October 14, 2025,” Institute for the Study of War, October 15, 2025, https://understandingwar.org/research/russia-ukraine/russian-offensive-campaign-assessment-october-14-2025/.
[6] “Defence Budget,” Aizsardzības Ministrija, accessed May 19, 2026, https://www.mod.gov.lv/en/about-us/defence-budget.
[7] “Implementation of the National Defence Budget,” Lietuvos Respublikos Krašto Apsaugos Ministerija, accessed May 19, 2026, https://kam.lt/en/facts-and-trends/implementation-of-the-national-defence-budget/.
[8] “Defence Budget,” Kaitseministeerium, accessed May 19, 2026, https://kaitseministeerium.ee/en/policies-and-development-defence-capability/national-defence-planning/defence-budget.
[9] ERR News, “Estonian Defense Forces Exercise Spring Storm 2026 Begins,” ERR, May 4, 2026, https://news.err.ee/1610013601/estonian-defense-forces-exercise-spring-storm-2026-begins.
[10] “Saber Strike 26 Strengthens NATO Alliance across Eastern Flank with Focus on Innovation and Interoperability,” DVIDS, accessed May 19, 2026, https://www.dvidshub.net/news/563338/saber-strike-26-strengthens-nato-alliance-across-eastern-flank-with-focus-innovation-and-interoperability.
[11] “Baltic Defence Line,” Riigi Kaitseinvesteeringute Keskus, January 19, 2026, https://www.kaitseinvesteeringud.ee/en/baltic-defence-line/.
[12] David Takacs, “Ukraine’s Deterrence Failure: Lessons for the Baltic States,” Journal on Baltic Security 3, no. 1 (June 1, 2017): 1–10, https://doi.org/10.1515/jobs-2017-0001.
[13] “Russia’s Hybrid Warfare Tactics Target the Baltics,” Jamestown Foundation, accessed May 19, 2026, https://jamestown.org/russias-hybrid-warfare-tactics-target-the-baltics/.
[14] “Russia’s Hybrid Warfare Tactics Target the Baltics,” Jamestown Foundation, accessed May 19, 2026, https://jamestown.org/russias-hybrid-warfare-tactics-target-the-baltics/.
[15] “Ministry of Defence of Latvia: Russia Carries out Information Operation against Baltics,” Aizsardzības Ministrija, March 27, 2026, https://www.mod.gov.lv/en/news/ministry-defence-latvia-russia-carries-out-information-operation-against-baltics.
[16] “The NATO Cooperative Cyber Defence Centre of Excellence Is a Multinational and Interdisciplinary Cyber Defence Hub,” CCDCOE, accessed May 19, 2026, https://ccdcoe.org/.
[17] Rain Ottis, Analysis of the 2007 Cyber Attacks against Estonia from the Information Warfare Perspective (Tallinn: CCDCOE, 2008), https://ccdcoe.org/uploads/2018/10/Ottis2008_AnalysisOf2007FromTheInformationWarfarePerspective.pdf.
[18] “EU-NATO Task Force: Final Assessment Report on Strengthening Our Resilience and Protection of Critical Infrastructure,” European Commission, accessed May 19, 2026, https://ec.europa.eu/commission/presscorner/detail/en/ip_23_3564.
[19] “Russia’s Hybrid Warfare Tactics Target the Baltics,” Jamestown Foundation, accessed May 19, 2026, https://jamestown.org/russias-hybrid-warfare-tactics-target-the-baltics/.
[20] “Chairman Risch Opening Statement at Hearing on Sabotage in the Baltic Sea,” United States Senate Committee on Foreign Relations, April 30, 2026, https://www.foreign.senate.gov/press/rep/release/chairman-risch-opening-statement-at-hearing-on-sabotage-in-the-baltic-sea.
[21] “Chairman Risch Opening Statement at Hearing on Sabotage in the Baltic Sea,” United States Senate Committee on Foreign Relations, April 30, 2026, https://www.foreign.senate.gov/press/rep/release/chairman-risch-opening-statement-at-hearing-on-sabotage-in-the-baltic-sea.
[22] VSquare, “From Kyiv to Riga: Russian Sabotage Operations in the Baltics,” VSquare.org, September 8, 2025, https://vsquare.org/russia-sabotage-operations-baltics/.
[23] VSquare, “From Kyiv to Riga: Russian Sabotage Operations in the Baltics,” VSquare.org, September 8, 2025, https://vsquare.org/russia-sabotage-operations-baltics/.
[24] “Strengthening Civil Preparedness in the Baltic Sea Region,” DIIS, August 29, 2025, https://www.diis.dk/en/research/strengthening-civil-preparedness-in-the-baltic-sea-region.
[25] “Home,” Kaitseliit, accessed May 19, 2026, https://kaitseliit.ee/en/.
[26] “Lithuanian Riflemen Union,” Lietuvos Šaulių Sąjunga, accessed May 19, 2026, https://www.sauliusajunga.lt/en/home.
[27] “National Defence Service,” Aizsardzības Ministrija, accessed May 19, 2026, https://www.mod.gov.lv/en/national-defence-service.
[28] “Increased Protection for the Civilian Population in the Baltic Sea and Nordic Region,” Government Offices of Sweden, accessed May 19, 2026, https://www.government.se/press-releases/2026/03/increased-protection-for-the-civilian-population-in-the-baltic-sea-and-nordic-region/.
