Ewa A. Andryjalowicz, M.A.

Can NATO respond to Russia’s attempt to destabilize its borders if it decides to test Article 5 of the North Atlantic Treaty? After years of growing Moscow’s aggression against Ukraine, the threat to the Baltic states and Poland is becoming more real than ever. The crucial question is: will the North Atlantic Alliance, with its requisite unanimity, be able to act quickly and effectively when a crisis becomes a reality?

Keywords: #NATO, #Article 5, #Defense & Security, #Baltic states, #Russia, #Ukraine, #NATO allies, NATO’s future, #U.S/EU relations

With the escalation of Russian aggression against Ukraine, relations with Russia have been frozen in the Baltic states, including Poland, since the annexation of Crimea in 2014. And with Russia’s full-scale attack on Ukraine in February 2022, relations between Russia and the West have deteriorated, and NATO’s eastern flank has once again become a focal point of the strategic debate. Although the North Atlantic Alliance has significantly strengthened its military presence in the Baltic states and Poland since 2014, and again after Russia’s full-scale invasion of Ukraine in 2022¹, the question of the actual “credibility” of Article 5 of the North Atlantic Treaty² remains relevant. This is particularly true in the context of limited, ambiguous, and hybrid scenarios that do not represent a “classic invasion” of NATO countries by Russia using “regular armed forces.”

Against this context, two areas of exceptional strategic and symbolic significance emerge: Narva – a city in northeastern Estonia³, predominantly inhabited by Russian-speaking people – and the Suwalki Gap, a narrow strip of land connecting Poland with Lithuania and Belarus to the east, linking the Baltic states with the rest of NATO. Kaliningrad, a Russian enclave between Poland and Lithuania, provides Russia with access from Kaliningrad to the so-called “NATO Lake.” Numerous analyses regularly identify these three regions as potential “flashpoints” where Russia could attempt to test the Alliance’s cohesion without an open declaration of war.⁴

The key difference, however, lies in the potential operation. In the case of Narva, it would be possible to exploit Moscow’s narrative of “protecting the Russian minority” or “preventing a humanitarian catastrophe,” analogous to Russia’s actions in Ukraine in recent years. In the case of the Suwalki Gap, Russia would not have a similar ethnic “pretext.” However, the Suwalki Gap would be of enormous military and logistical importance to Russia, as its temporary blockade could cut off the Baltic states, including Poland, from land support from other NATO countries, simultaneously hindering their military operations.⁵

The purpose of this article is to answer three fundamental questions:

• First, why might Russia decide to test NATO’s so-called “red lines” in Narva or the Suwalki Gap region?
• Second, what are the realistic geographic and military considerations for such operations?
• And third, how would NATO likely respond to a Russian attack, and would triggering Article 5 be politically and practically possible?

By analyzing the political, demographic, and operational aspects of both regions, this article will assess which scenario is more likely and whether NATO is genuinely prepared to undertake a likely limited but dangerous collective defense effort.

1. Russia’s Motivations: Strategic Testing of NATO. The Narva and Suwalki Gap as a Potential “Red Line” Area

Russia has been using hybrid warfare tactics for years, allowing it to achieve political goals without launching a full-scale war. Why might Moscow want to test NATO in both regions?

Narva

The city of Narva, located in Ida-Viru County, in northeastern Estonia, may hold a special place in Russia’s strategic imagination. And why?

• First, it could serve as a pretext for Moscow’s demographic policies. Over 80-90 percent of its inhabitants are Russian-speaking⁶, some of whom hold Russian citizenship or are stateless. This demographic configuration creates ideal conditions for Moscow to deploy a narrative, such as “protecting compatriots,” and could serve as a pretext for intervention in the name of “protecting ethnic minorities.” This narrative has been repeatedly used by the Kremlin to justify military interventions, as has been the case in Crimea and other regions of present-day Ukraine.⁷

• Second, Russia would have another pretext to test NATO’s cohesion, based on its observation of varying degrees of involvement from NATO members in supporting Ukraine during the early stages of the invasion. Ukraine, not being a NATO member and having given up its nuclear weapons⁸ following the Budapest Memorandum of 1994⁹ (signed by the U.S., U.K., and Russia), provided the Kremlin with a clear opportunity for a full-scale attack, knowing that NATO states would not directly intervene.

At the same time, observing the slowed decision-making by the European Union and the varying degrees of involvement of NATO members—currently limited to so-called “a coalition of countries willing”¹⁰ to aid Ukraine, excluding some countries like Hungary, among others—the Kremlin could have perceived this as a sign of weakness and believed that NATO would not trigger Article 5 of the North Atlantic Treaty in the event of an attempt to seize Narva.

The lack of a swift, decisive, and coordinated response to Russia from the beginning of the war, and the delays in providing aid to Ukraine in the crucial initial phases of the conflict, could be interpreted by the Kremlin as a “political and military weakness” on the part of the EU, and especially NATO. This perception could lead the Russian Federation to test further the cohesion of the Alliance and the credibility of NATO’s deterrence mechanisms, particularly on its eastern flank, including in the context of a possible intervention in the Narva region.

• Third, Russia could use the same pretext as in Ukraine in a potential attack on Narva, Estonia. Given the possible reluctance of some NATO members to engage directly in an armed conflict with Russia, the Alliance’s response could be delayed or limited in scope, particularly in the political decision-making process in NATO allies’ parliaments and under intense public opinion pressure in these countries.

The Kremlin could perceive a potential attack on Estonia in the Narva area as a strategically rational action, with a relatively low risk of escalation. This belief stems from the city’s unfavorable geographic location—immediately adjacent to the Russian Federation and close to Belarus—which might lead the Russian authorities to believe NATO would not respond militarily.

Moreover, in a scenario involving a simultaneous attack on the Narva region and a blockade of the Suwalki Gap, or operations launched from the Russian enclave in Kaliningrad, NATO could face significant challenges in conducting a land operation, making it potentially unfeasible in the short term. In such circumstances, Moscow could decide to undertake such a maneuver primarily to reassess NATO member states’ reactions—especially key geopolitical players such as the United States, Germany, France, and the United Kingdom.

It is worth emphasizing that Russia has been conducting intensive information and cyber operations against Estonia for many years. Estonia, which borders the Russian Federation directly and was part of the Soviet Union before the USSR’s collapse, has experience of Soviet occupation, which significantly shapes its perception of security threats. The 2007 cyberattacks targeting Estonian state institutions, the banking sector, and the media were among the first examples of a coordinated cyberwarfare operation against a NATO member state. Not only cyberattacks but also disinformation operations could become a greater problem for Estonia and, consequently, for the Alliance, as such operations provide Russia with a platform to create chaos without having to engage troops in conventional warfare.

These events prompted a significant strengthening of Estonia’s cybersecurity systems, especially given the increasingly sophisticated nature of threats in this domain. Since then, Narva has regularly appeared in Russian media as an alleged example of discrimination against Russian-speaking people, which the Kremlin could potentially use as a pretext to intensify its actions against the region. At the same time, such actions could test the reactions and decision-making coherence of NATO member states, especially amid the United States’ weakened support.¹¹

From the Kremlin’s perspective, a key advantage of Narva could be the ability to conduct operations below the threshold of open armed conflict, for example, through social provocations, the use of local militias, cyberattacks, disinformation campaigns using drones, and the broadly defined instruments of hybrid warfare, which have long been a component of Russia’s influence strategy. Such a scenario would force NATO to make ad hoc decisions and quickly resolve a fundamental dilemma: whether to treat external aggression or an internal security crisis within a member state as the primary threat. Consequently, the question arises whether such actions would justify the initiation of Article 5 of the North Atlantic Treaty.

Given political divergences and public pressure regarding an offensive, rather than defensive, approach towards Russia, the North Atlantic Alliance’s intervention in Narva could be limited. Such a limited response would force NATO member states to decide whether to activate Article 5, simultaneously allowing Russia to test both the Alliance’s political cohesion and its actual readiness for action.

In practice, however, triggering Article 5 is not automatic and requires consensus among NATO allies. If the majority of NATO members were unwilling to engage in direct war with Russia, the Alliance could limit its response to symbolic actions, economic sanctions, or logistical support for Estonia, rather than a full-scale military intervention. These decisions would depend on a calculated risk of conflict escalation, including the potential use of nuclear weapons. As a result, although Article 5 theoretically applies, its practical implementation could be limited, simultaneously testing Russia’s political cohesion and NATO’s readiness to act.¹²

The answer to the first question might seem straightforward, as Russia’s motivations and justifications for potential actions in the Estonian region of Narva could open the door to operations beyond hybrid, cyberattacks, disinformation, or military tactics.

Suwalki Gap

The Suwalki Gap is a key element of NATO’s security architecture on the eastern flank, serving as the only land connection between the Baltic states—Estonia, Latvia, and Lithuania—and Poland and other Alliance structures. Losing control of this area would isolate the Baltic states from NATO military support and significantly worsen their security situation.

For Russia, closing the Suwalki Gap would be a challenging military-strategic operation. Unlike potential operations in the Narva region, this area is located in the immediate vicinity of several NATO members, significantly increasing the likelihood of an immediate military response from the Alliance. A potential Russian takeover of the corridor would require simultaneous, coordinated operations conducted from the Russian enclave of Kaliningrad and Belarus. Moreover, the Suwalki Gap could prove a complex operational area for Russia, as NATO forces’ high readiness and presence make it highly protected. Any Russian attempt to change the status quo in this region would be clearly interpreted as overt aggression against NATO and would carry a high risk of violent escalation of the conflict, including the real prospect of a full-scale war.

Unlike Narva, the Suwalki Gap does not provide Russia with a convenient ethnic or humanitarian pretext—its significance is solely strategic and military. Blocking or controlling this area, even for a short period, could seriously hinder NATO’s ability to deploy ground forces to Lithuania, Latvia, and Estonia, and, for Moscow, would signal its ability to escalate and rapidly demonstrate the Alliance’s logistical limitations. Simulations from a U.S. global policy think tank, RAND, and geopolitical analyses indicate that Russia could attempt to seize this area within a matter of hours, underscoring Russia’s strategic vulnerability and NATO’s potential logistical challenges.¹³

However, an operation in this region would carry very high political and military risks. Any Russian action in the Suwalki Gap would mean confrontation with Poland and Lithuania, as well as the near-simultaneous involvement of NATO allies, including those from Scandinavia (Sweden, Denmark, and Finland). The lack of a “humanitarian narrative” would make it impossible to conceal the operation’s offensive nature. Although the Suwalki Gap remains a weak point for NATO, significant deterrence elements currently limit the feasibility of a Russian offensive, unless Moscow deliberately seeks to provoke NATO into invoking Article 5 to test the Alliance’s response—a scenario far less likely than an attempted seizure of Narva.¹⁴

2. Geographical and Military Conditions of Possible Military Operations on NATO’s Eastern Flank

Narva is a city in eastern Estonia, located on the Narva River, which forms the direct border with the Russian Federation. The town lies right on the state border, opposite the Russian city of Ivangorod. The Narva River connects Lake Peipus with the Gulf of Finland in the Baltic Sea.

The proximity of the Russian border, the ease of operational access, and the region’s limited local defense capabilities increase its vulnerability to military and hybrid pressure from the Kremlin. From a military perspective, Narva is a relatively easy target: its location allows for the rapid deployment of forces and direct logistical support from Russian territory, without the need for lengthy operations. Estonian armed forces are small, and their ability to independently repel a sudden, local operation remains limited.

Picture from https://www.dw.com/en/narva-the-eus-russian-city/a-48878744

NATO maintains an enhanced military presence in Estonia, but it is primarily deterrent in nature rather than full-scale defensive.¹⁵ Any reinforcements would have to be delivered by sea or air, which could be significantly delayed if Russia were to intensively deploy its A2/AD (anti-access/area denial)¹⁶ capabilities. Furthermore, a simultaneous closure of the Suwałki Gap by Russia would cut off Lithuania, Latvia, and Estonia from NATO land support, including in the Narva area. Therefore, this area should be included in analyses of potential escalation scenarios and the Kremlin’s potential crossing of further “red lines.”

Suwalki Gap

The Suwalki Gap is a strategic strip of land, 40-60 miles long, located on the border of Poland and Lithuania, separating the Kaliningrad Oblast, a Russian enclave, from Belarus. It is crucial to NATO security because it provides the only land route for troop transport to the Baltic states (Lithuania, Latvia, and Estonia), ensuring their connectivity with Poland and the rest of the North Atlantic Alliance. Potential Russian control of this area could isolate the Baltic states from NATO support.

Picture: Map of the Suwalki Corridor – Credits: Globalsecurity.org from The Atlas Report Geopolitical Analysis

from: https://atlas-report.com/what-is-the-suwalki-gap-natos-most-vulnerable-region-in-europe/

It is worth noting that the Suwalki Gap is characterized by rugged, forested terrain, limited road infrastructure, and a high level of surveillance. It is one of the most reconnaissance areas of NATO’s eastern flank, regularly exercised as part of allied maneuvers.

Any attempt to seize the Suwalki Gap would require coordinated operations conducted simultaneously from the Russian enclave of Kaliningrad and Belarusian territory, effectively a joint operation. Such an undertaking would be difficult to conceal, quickly detectable, and would almost immediately trigger NATO’s response mechanisms, carrying a high risk of escalation into a large-scale conflict. For this reason, Russia would likely refrain from such a move, avoiding the role of being the first to enter the open “NATO battlefield.” NATO members could clearly interpret such a move as a declaration of war.

Instead, the Russian Federation could preferentially adopt a strategy of prolonged pressure and provocation, teetering on the brink of escalation as long as these actions remain tolerated—though not necessarily accepted—by NATO allies. This logic would assume continued provocative actions until NATO’s response took the form of an open military response.¹⁷ Such a response could be portrayed by Moscow as an act of aggression against Russia, potentially serving the political interests of the current Kremlin leadership. In such a scenario, the Kremlin would gain a powerful propaganda tool to mobilize society, strengthen the morale of the armed forces, and legitimize government decisions through the narrative of Russia as a “victim” forced to defend itself against alleged NATO aggression.

3. NATO’s Response to the Russian Threat: Article 5 Dilemmas and Strategic and Political Consequences

NATO’s response to Russian aggression, particularly in defending regions such as Narva or the Suwalki Gap, requires not only appropriate operational capabilities but also the political will of member states. Therefore, it is worth analyzing the mechanisms for invoking Article 5 of the NATO Treaty and the challenges related to decision-making within the Alliance.

A key question remains whether NATO would decide to invoke Article 5 in the event of Russian aggression in the Narva or Suwalki Gap regions. As is known, the NATO Treaty does not clearly specify the form of attack on a member state of the North Atlantic Alliance, leaving room for interpretation and political disputes within the Alliance.¹⁸

• First, in the case of hybrid “warfare,” drone attacks, or cyberattacks, NATO’s Article 5 has not yet been implemented, although these are also forms of attack and violation of the airspace or cyberspace of NATO member states. NATO has faced such incidents numerous times in recent years, and in recent months, these forms of attacks have become almost daily, particularly in the context of Russia’s actions against NATO member states. These attacks were and remain likely aimed at weakening the Alliance, testing member states’ responses to such threats, and testing governments’ decision-making readiness and public opinion’s reaction to such “incidents.”¹⁹

• Second, implementing Article 5 of the North Atlantic Treaty is not as simple as it might seem. While it provides the basis for the collective defense of NATO member states, it isn’t an automatic defense mechanism. The decision to implement it requires a political process and the consent of all Alliance members. In practice, a member state that becomes the target of an attack reports this fact to the Alliance. From that moment on, NATO triggers the entire decision-making process.²⁰

Consultations under Article 4 of the NATO Treaty allow members to discuss the situation. Based on the consultations’ results, the North Atlantic Council (NAC)²¹ decides whether to implement Article 5. However, crucially, this decision is not automatic – it is a political process in which each member state has the right to vote. For this reason, one member state can block the response, thereby exercising its veto.

If a decision is made to implement Article 5, all member states will consider the attack a threat to the entire Alliance. As a result, each member will take appropriate action—including the use of force—to assist the attacked ally. It is important to emphasize that ignoring an attack on one member state could seriously undermine NATO’s credibility, threaten the Alliance’s unity, and compromise its ability to respond to threats, thereby posing a challenge to NATO’s integrity and its ability to defend itself effectively.

• Third, in the case of Narva, an intense debate could arise over the proportionality of the response and the risk of escalation. Russia could expect a delay in decision-making and differences of opinion among member states. An attack on the Suwalki Gap, on the other hand, would almost certainly trigger Article 5 immediately, as the threat would be unequivocal and would affect key Allied infrastructure, but would this actually happen? NATO countries not located on the eastern flank could react to such a situation with a delay, triggering Articles 3 and 4, and conducting lengthy consultations within the North Atlantic Council (NAC). The North Atlantic Council (NAC) decides to implement NATO’s Article 5, and member states may delay it due to political factors or public pressure, thereby delaying the rapid implementation of joint defense action. The North Atlantic Council (NAC) is NATO’s principal decision-making body, responsible for political and military decision-making. It was established under Article 9 of the North Atlantic Treaty²² and is the only body authorized to establish subsidiary committees. The NAC oversees security-related processes within the Alliance and is responsible for implementing NATO policy. NAC members make decisions unanimously, ensuring the full support of all member states. Representatives hold meetings at various levels, from Permanent Representatives to Heads of State and Government, and the Secretary-General chairs them. Each country retains sovereignty in its decision-making, and representatives act according to instructions issued by their governments.

From Russia’s perspective, any form of aggression or pressure on NATO member states can be viewed as part of a broader strategy aimed at undermining the Alliance’s unity and testing its response to threats.

For Moscow, this would be a strategic maneuver to test the Alliance’s response. The Kremlin could seek to undermine NATO unity, weaken member states’ economies through economic pressure, polarize public opinion, and destabilize public sentiment, exploiting political differences within the Alliance. It would especially apply to those circles and political elites that tend to favor dialogue and economic cooperation with Russia over open confrontation and the use of force.

Moscow could also opt—with nothing to lose—for escalation and open confrontation with Alliance members, a course and its consequences that could spiral out of control, primarily on NATO’s side. Already during the pressure phase, the Alliance incurs measurable operational costs, including significant expenses related to the frequent scrambles of standby fighter pairs, such as MiG-29s²³ and F-16s²⁴, operating, e.g., from bases in Poland.

The scrambles of standby fighter pairs alone generate high operational costs, amounting to thousands of dollars per flight hour for each aircraft, as well as additional burdens related to maintaining combat readiness and logistical support. A typical mission by a single pair of fighters, lasting one to two hours, can cost USD 20,000-60,000, with costs rising significantly for more extended missions or the involvement of additional support units, according to estimates.²⁵ Maintaining a high level of combat readiness for extended periods imposes significant budgetary burdens, which, in the long term, could constitute a further instrument of pressure on Alliance member states.

After the Russian attack on Ukraine in February 2022, NATO took a series of steps to strengthen the Alliance’s defense and prepare for potential threats. At the 2023 Vilnius Summit, NATO leaders approved a new generation of regional defense plans, establishing the Allied Reaction Force (ARF)²⁶, which became operational on July 1, 2024. The ARF replaced the NATO Response Force (NRF) under the new NATO Force Model, offering a more flexible, high-readiness force better adapted to modern threats.

Two years later, at the 2025 summit in The Hague, NATO member states committed to investing 5% of GDP annually in defense until 2035, which requires significant investments in the defense industry, equipment acquisition, and the development of new defense and deterrence plans. Expanding the defense industry and increasing production are intended to address logistical and procurement challenges.²⁷

What should NATO allies do now in the event of a threat in the Narva and Suwalki Gap region if Russia attacks?

First, NATO should narrow the definition of “attack” under Article 5 of the North Atlantic Treaty. A precise definition is essential because some member states may interpret the threat selectively. For example, in the case of an attack on regions like Narva, they might argue that it is merely an “internal matter” due to the presence of Russian citizens in the area. The lack of a clear definition would allow Russia to manipulate the situation, slow NATO’s response, and delay the mobilization of the Rapid Reaction Force, thereby threatening the Alliance’s territorial integrity.

Second, despite economic sanctions, Russia has found new channels of cooperation with non-Western countries, including the BRICS countries²⁸, and in particular China, India, and Iran, allowing it to maintain economic and military ties. Many European Union countries continue to import energy resources from Russia, albeit indirectly, which weakens the effectiveness of sanctions. To improve the effectiveness of sanctions, NATO should strengthen international coordination for their enforcement and for controlling the flow of resources. Furthermore, NATO members should cease indirectly purchasing energy resources from Russia and focus more on diversifying energy sources. Increasing imports of liquefied natural gas (LNG)²⁹ from the United States could improve the Alliance’s energy security and strengthen transatlantic economic and political relations. Although American gas is more expensive, its stable and reliable supply is crucial for regions vulnerable to Russian aggression.³⁰

Third, NATO member states must allocate at least 5% of their GDP to defense, as agreed at the recent NATO summit. Increasing defense spending will enable faster modernization of military equipment, the development of new technologies, and the provision of adequate supplies and logistical infrastructure to prepare for potential crises. This spending is urgently needed to ensure the Alliance maintains its combat readiness amid the growing threat from Russia. Finally, NATO should invest in developing new defense technologies, such as drones and missile defense systems, and in expanding its cyber infrastructure. Modern threats, such as cyberattacks and drone attacks, require advanced technology. NATO must focus on a faster and more precise response to new forms of aggression, especially in cyberspace. Only by developing these technologies will the Alliance be able to effectively defend itself against modern threats that may become part of hybrid warfare.

Final Conclusions

The analysis indicates that while both scenarios—an attack on the Narva River and the Suwalki Gap—are theoretically possible, Narva is a more realistic and politically practical target for Russia to test NATO’s Article 5. While the Suwalki Gap remains a key strategic area, attacking it would almost certainly trigger open conflict with the entire Alliance. Ultimately, NATO’s deterrence depends not only on its military presence but also on its ability to make rapid political decisions amid ambiguity.

In the context of a potential threat, the political will of Allied countries and the pressure exerted by public opinion, which can influence government decisions, also play a crucial role. In moments of crisis, there should be no room for political divisions—different political parties should not block the response, and the entire political scene should unite in defense of one NATO member state. Only by demonstrating unity and determination can the Alliance effectively deter Russia from continuing its aggression against Narva or the Suwalki Corridor.

It is also essential to strengthen political consensus within NATO to enable faster decision-making and more effective responses in moments of crisis. Unity in making rapid, unanimous decisions will not only strengthen NATO’s credibility but also send a strong signal to the Kremlin that the Alliance is strong, decisive, responsive, and able to act in complete harmony, regardless of political differences within individual states. Such a stance will be the most significant deterrent against further attempts to destabilize the region.

BIO

Ewa A. Andryjalowicz, M.A., is a Researcher, Analyst, and Advisor at the State Parliament in Germany. A multilingual international affairs professional with several years of research experience in Defense and Security Policy, concentrating on transatlantic (E.U./U.S.) with a concentration on Poland/U.S., and Germany/U.S. long-term collaboration and NATO’s Future.

She can be found on LinkedIn or contacted via e-mail: eandryjalowicz@gmail.com