Irreconcilable Differences? NATO's Response to Russian Aggression Against Ukraine

Abstract

With Russia's full-spectrum war in Ukraine, NATO is rethinking its force posture and responding in ways that are consistent with its norms and identity as an alliance. While the war has been framed by some as a vindication of structural realism, we instead revisit constructivist arguments about security communities. This literature, which foregrounds learning and socialization processes, advanced scholarly and policy debates from NATO enlargement to defence sector reform. By contrast, how security communities engage with adversaries has received less attention. Noting the obvious balancing dynamics on display, we emphasize how threats take on particular meanings, which shape the types of military options considered. We also provide an explanation for NATO's resilience in the face of this external shock. Alliance disunity notwithstanding, we argue that collective defence is being redefined in real time, through dynamics that are not exclusively bound by a narrow focus on the military threat posed by Russia.

Russia's invasion of Ukraine on 24 February 2022 may have shocked the world, but the war was close to a decade in the making. Indeed, Moscow's preferred response to the Euromaidan Revolution was the imposition of sudden, though limited, fait accomplis in Crimea and the Donbas region of Ukraine. What Russia did in 2014 shaped expectations at NATO, and elsewhere, predicting (wrongly) a continued exploitation of the gray zone, rather than all-out war. After all, strategic interactions after the annexation of Crimea were focused on hybrid warfare below the threshold of active conflict. On this front, the Kremlin successfully deceived Ukraine and the West. In the end, that might prove to be Putin's only strategic success. Still, the terms of Europe's security architecture have been redefined, forcing some adaptation on the part of NATO, the EU, and individual countries, especially the US. ¹ While NATO was already on its way to doing so with the planned release of the 2022 Strategic Concept, it reiterated, if not consolidated, its stance with the 2023 Vilnius Summit. For some IR scholars, the Russian assault represents a vindication of structural realist thinking about the balance of power and the inescapably tragic logic of great power politics. Yet, as we argue, key aspects of NATO's response to Russian aggression are best understood within a constructivist framework of analysis. Indeed, with the war in Ukraine, NATO is required to rethink its force posture, but also the types of actions that are compatible with its identity as a political-military alliance grounded in a specific set of norms.

We suggest that, to understand the Alliance's interpretation of—and response to—the Russian aggression against Ukraine, it is particularly helpful to draw from the constructivist literature on security communities. ² This literature foregrounds learning and socialization processes, while advancing scholarly and policy debates on NATO's future. Yet, how security communities engage with adversaries has received comparatively less attention. This issue is central to our analysis. By focusing on NATO's adaptation to the 2022 Russian invasion of Ukraine, we aim to advance academic and policy-related understandings of the current war and its implications for international security, and, more broadly, to contribute to theory refinement on security communities in this crucial historical moment. In this instance, a constructivist account drawing on the security communities literature certainly takes note of the current (re)turn to a collective defence focus within the Alliance, but emphasizes how threats take on particular meanings that then shape political responses and the types of military options considered. Importantly, a constructivist take also provides an explanation for NATO's resilience in the face of this external shock. For example, the Alliance's varied relationships, embodying a community of practice made up of allies, partners, civil society actors, and private-sector stakeholders, contributes to NATO strength in a way that narrow assessments of economic and military indicators obscure. At the same time, a constructivist approach enables a sophisticated understanding of the challenges faced by NATO member states in maintaining cohesion in a rapidly changing security environment. Against the background of an analysis of both unity and challenges to cohesion, we argue that collective defence is being redefined in real time, through dynamics that are not exclusively bound by a narrow focus on material capabilities.

The transatlantic security community and its dangerous other

Russia's invasion of Ukraine forced NATO to adapt very quickly to what Secretary General Jens Stoltenberg has called a “more dangerous and competitive world.” ³ At the Vilnius Summit, NATO member states restated key language from the Strategic Concept, namely that “the Russian Federation is the most significant and direct threat to Allies’ security and to peace and stability in the Euro-Atlantic area.” ⁴ As expected, the 2022 concept marked NATO's strong re-orientation towards its traditional function of collective defence, as per Article 5 of the Washington Treaty. Deterrence and defence were identified as one of the three core tasks, which together reinforce collective defence. ⁵ Revealingly, the Strategic Concept

reaffirms that NATO's key purpose is to ensure our collective defence, based on a 360-degree approach. It defines the Alliance's three core tasks: deterrence and defence; crisis prevention and management; and cooperative security. We underscore the need to significantly strengthen our deterrence and defence as the backbone of our Article 5 commitment to defend each other.” ⁶

This, after many years in which out-of-area crisis management occupied much of the Alliance's attention and resources.

The Strategic Concept, therefore, stands in sharp contrast to what the 2010 version envisioned:

NATO-Russia cooperation is of strategic importance as it contributes to creating a common space of peace, stability, and security. NATO poses no threat to Russia. On the contrary: we want to see a true strategic partnership between NATO and Russia, and we will act accordingly, with the expectation of reciprocity from Russia. ⁷

Even Putin, early in his presidency, expressed optimism regarding the NATO-Russia relationship, stating that “only by harmoniously combining our actions…will we open up wide-ranging possibilities for building a single security region—from Vancouver to Vladivostok.” ⁸ Over the course of two decades, then, the relationship that NATO had hoped to cultivate with Russia went from promising to abysmal. NATO's solidarity with Ukraine appears unequivocal and its relationship with Russia, irreparable.

While the Western allies’ military response has not met all Ukraine's demands, it has, nevertheless, been impressive. Unsurprisingly, the US is in the lead with over 70 billion EUR in total assistance, with half going to military assistance alone. ⁹ What the US and NATO are still not prepared to do, however, is to impose a no-fly zone or engage in other actions that, in the allies’ eyes, could trigger direct confrontation with Russia. Rather than withdraw forces from Central/Eastern Europe as Putin had demanded, NATO moved quickly to significantly upgrade its posture through enhanced Forward Presence; member states and partners also boosted weapons shipments to Ukraine, delivering increasingly sophisticated weapons platforms as the war intensified and then endured. Initial packages ranged from the basic—rifles, ammunition, helmets, Kevlar vests, artillery shells, and grenade launchers—to the sophisticated—Stinger antiaircraft missiles, US Javelin anti-tank missiles, Swedish AT-4 rocket launchers, British next-generation anti-tank weapons, and armed drones. Tanks and fighter jets came next, overcoming intra-alliance disagreements about where the line should be drawn in offering lethal capabilities.

Furthermore, at the 2023 Vilnius Summit, NATO members agreed to streamline Ukraine's NATO membership process. The allies have again promised Ukraine—now widely recognized within NATO as a country that is fighting for the values of the security community—that its future is in the Alliance. First, they agreed to remove the requirement for a Membership Action Plan, changing Ukraine's membership path from a two-step to a one-step process. Second, the Allies established the NATO-Ukraine Council, a joint body of equals for consultation and decision-making. Third, Allies committed to a multi-year support program for Ukraine, covering critical needs like de-mining equipment, fuel, and medical supplies. Stoltenberg explained that “the NATO programme will also focus on building interoperability and ensuring that Ukraine transitions from Soviet equipment and doctrine to NATO standards.” He also clarified that Allies and partners would need to continue providing Ukraine with the military assistance it needs to prevail, and reaffirmed NATO's commitment to stand by Ukraine for as long as it takes. ¹⁰

There has been no shortage of academic analyses and debates taking stock of these changes affecting the transatlantic security equation. One of the most influential set of voices has interpreted the war as vindication of structural realist thinking about the inescapable logic of power-balancing, the tragedy of international politics, and the folly of ignoring the interests and security concerns of great powers. Indeed, one of the most prominent contemporary structural realist scholars, John Mearsheimer, was arguing as early as 2014, following Russia's first invasion of Ukraine, that this conflict was the “West's fault.” According to Mearsheimer, it was “the liberal delusions” of Western leaders that had “provoked Putin.” ¹¹ But, of course, there is much more to this story. While a full analysis of reasons that led Putin's Russia to engage in aggression against Ukraine is beyond the scope of this article, we suggest that the structural realist line of argument famously articulated by Mearsheimer loses sight of important factors, including Putin's perceptions of humiliation from the breakup of the Soviet Union and a state of near economic collapse in Russia—factors that were not caused by the West. ¹² Indeed, it is difficult to conceive that, without enlargement, Russia's relationship with NATO would have flourished. It is also worth recalling that, prior to the 2014 Russian annexation of Crimea, NATO maintained a very light military footprint on its eastern flank, posing no threat to Russia.

In the aftermath of Russia's 2022 invasion of Ukraine, the institutional mechanism supporting collective defence at NATO was activated, not because any individual ally was under imminent threat of Russian invasion. Rather, what was at stake in the allies’ view was not just a regional conflict between Ukraine and Russia but a broader challenge to the core values and norms inscribed in the security community represented by NATO. To understand NATO's response to this crisis, therefore, it is useful to draw on the literature on security communities.

The literature on security communities has its roots in the 1950s work by Karl Deutsch and his colleagues, who argued that the North Atlantic area had emerged as a security community—a place where a group of countries has agreed to resolve common social problems through a process of peaceful change. ¹³ Several decades later, a host of constructivist scholars placed the concept of security community at the heart of a new body of literature that challenged realist and liberal assumptions about international politics. In the constructivist definition, security community represents “a transnational region comprised of sovereign states whose people maintain dependable expectations of peaceful change,” where “peaceful change” indicates “neither the expectation of nor the preparation for organized violence as a means to settle interstate disputes.” ¹⁴ Constructivists rely on three inter-related concepts—identity, trust, and practice—to conceptualize security community. This involves a convergence of: shared identity grounded in specific norms and values; trust that members of the community will respect those norms and only engage in certain types of behaviour vis-à-vis one another; and practices through which the community is reproduced and, under certain conditions, expanded. The logic here is not absolute; it is not meant to suggest that norms and values are never called into question or contested, but that there are dependable mutual expectations for how members of the community act and that certain practices are triggered when transgressions appear likely.

In the case of the transatlantic security community, constructivists conceptualize the shared identity as grounded both in liberal-democratic norms of internal politics and in norms of how member states should behave toward one another: engaging in self-restraint, dialogue, and consultation, and treating security among them as indivisible. ¹⁵ This normative foundation generates trust that disputes among member states will not lead to violence, that key decisions will be made based on consultation and cooperation, and that any attack on one ally will be treated as an attack on all. ¹⁶ One may recall how the NATO secretary-general intervened to mediate the tensions between Greece and Turkey, which included the introduction of a bilateral military de-confliction mechanism. ¹⁷ And in the current standoff with Russia, allied leaders and NATO leadership have reiterated the mutual defence clause of Washington Treaty's Article 5, underscoring its importance in the lead-up to and following the invasion. Both discursively and in terms of the actions taken, then, the idea of security indivisibility is at NATO's core.

Among constructivist scholars, there is broad agreement that NATO represents the institutional expression of one of the most successful, mature security communities in history. Within this community, there is a sense of “we-ness” as well as trust that, whatever their differences, community members will respect common liberal-democratic norms. To understand how such a community adapts to various changes and challenges, and under certain conditions also expands, many constructivist scholars have focused on the concept of practices. Practices are “knowledge-constituted, meaningful patterns of socially recognized activity embedded in communities, routines, and organizations that structure experience.” ¹⁸ In an influential article, Emanuel Adler described security communities as communities of practice, which spread through the co-evolution of background knowledge and subjectivities of self-restraint. ¹⁹ Focusing on the transatlantic area, he argued that the successful expansion of the security community from a core of Western states to Central and Eastern European countries (CEECs) during the 1990s, and the mainly unsuccessful later attempts to change the broader Middle East, were underpinned by a “cooperative-security” community of practice, which, growing from the Helsinki Process, endowed the European Union (EU) and NATO with “the practices necessary for the spread of social structure.” ²⁰

Security communities, constructivists argue, are sustained by specific sets of practices. First, and as noted above, dependable expectations of peaceful change are based on the practice of self-restraint, revolving around the abstention from the use of force. ²¹ Second, actors that constitute a security community engage in common enterprises, projects, and partnerships, thereby turning security community into the day-to-day practice of peace. Third, cooperative security is the “natural security practice of security communities.” Fourth, diplomacy and “norms of consultation and multilateral decision-making practices” underpin normal practices among members of the community, to the exclusion of violent confrontations. Their key role is to institutionalize reassurance, and thus enhance trust within the community. Fifth, there is a “disposition towards spreading the community outward through explicit or implicit practices of socialization or teaching.” ²² To this end, NATO's partnerships further embody the Alliance's cooperative security dimension. NATO uses its convening power to host regular meetings and to develop best practices in functional areas of cooperation, consistent with the logic of socialization and teaching. These partnerships contribute to the diffusion of NATO norms and values in a context of increasing polarization and globalized security challenges.

Constructivist thinking about security communities, we suggest, is uniquely well suited to capture the dynamics at play and corresponding meanings that were crystallized through day-to-day practices from the 1990s to today. Material explanations are at a loss to account for why the Alliance would keep “making more commitments, and creating a steady flow of new members, all the while downsizing its overall military capabilities.” ²³

NATO vs. Moscow: Quo vadis?

The constructivist literature, and work on security communities in particular, advanced scholarly and policy debates on NATO enlargement, security sector reform, and partnership building. By contrast, the question of how security communities in general and the transatlantic Alliance in particular engage with adversaries has received comparatively less attention. While the hope that engagement with Russia could have changed the terms of its relationship with NATO was decisively crushed in 2022, what seems clear, even as an early assessment of the war, is that a more positive outcome would have required that both parties, NATO and Russia, swap their deterrence mindset in favour of cooperative security. The intersubjective understanding that took hold in the NATO context did not extend beyond member states. Echoing Adler, it was never “normalized” through NATO-Russia interactions, despite the presence of institutional structures to support these. ²⁴

A lesson in failure can be found in the attempt to build a cooperative relationship with Russia. Particularly revealing, in this context, is the evolution of the NATO-Russia Council. From Russia's perspective, the NATO-Russia Council did not emerge as a persuasive solution to regional insecurity on the Eastern flank, stunting the potential for a common interpretation of the relationship's terms. In theory, at least, the Council could have served as a forum for fostering a change away from competitive and individualistic interactions to cooperative security systems “in which states identify positively with one another so that the security of each is perceived as the responsibility of all,” holding the potential for the parties to break free from the dictates of self-help behaviour and the destructive patterns which security dilemmas impose. ²⁵ This approach to Russia was linked to NATO's post-Cold War focus on promoting international security via a Kantian-inspired cultural approach. To understand this, it is useful to draw on the work of Michael Williams and Iver Neumann. In their influential 2000 article, Williams and Neumann shed important light on NATO's post-1989 characterization of threats and adversaries in cultural, rather than geostrategic terms. This, they argue, was central to NATO's ability to adapt to the end of the Cold War and the disappearance of the Soviet enemy. ²⁶ In an environment marked by the collapse of the Soviet bloc and the eruption of violence linked to ethnic conflict (most notably in the former Yugoslavia), there was a shift away from definitions of security focused on military power, and toward a heavy emphasis on liberal-democratic governance within states. On this logic, while there was no clearly identified enemy state, developments within the transient and (potentially) unstable former communist countries could threaten regional security. The prevailing view in NATO was that the promotion of stable liberal democratic norms would be vital for international stability in the new era. ²⁷ In that context, NATO embarked on efforts to build new norms of trust and cooperation even with its former adversary—most notably, as noted above, via the establishment of the NATO-Russia Council in 2002.

Those efforts, however, did not produce the intended outcome. Instead, NATO was faced with an ever more authoritarian Russia, which, under President Putin, came to challenge the key values of the transatlantic security community and, more broadly, the core norms of the post-1945 international order. A key moment in the redefinition of relations with Russia was Moscow's 2014 aggression against Ukraine and illegal annexation of Crimea. At that time, the Alliance acted in a cohesive and deliberative manner—as a mature security community would—to collectively (re)securitize Russia, seeing it as a threat to NATO and their partners. One of the most important analyses of these developments was provided by Mark Webber and James Sperling. ²⁸ As they argued, in response to Moscow's illegal annexation of Crimea, NATO acted as both a site and as an agent of successful “collective securitization” involving “a return to Cold War policies and discourse, albeit shaped by the experience of the intervening decades.” ²⁹

In that context, NATO shifted its discourse on Russia, identifying it as a source of danger. By acting in direct violation of the norms that it had promised to uphold in the post-Cold War period, Moscow challenged the stability of the Euro-Atlantic region, contravened international law, and “gravely breached the trust upon which cooperation” with NATO had been premised. Then NATO secretary general Anders Rasmussen suggested that Crimea was a “game-changer.” ³⁰ Commensurate with this change in discourse, which emphasized the violation of norms and trust, NATO also revised its policies toward the (re)securitized source of threat. It suspended all practical civilian and military cooperation with Russia and also adopted a series of follow-on measures that fall into two categories, defined by NATO as “assurance” and “adaptation”’—effectively amounting to a significant reinforcement of the Alliance's collective defence function. The collective resecuritization was taken to a new level following the 2022 invasion of Ukraine, when it became clear that, far from abandoning its aggressive stance, Moscow was accelerating its open violation of the rules-based international order, engaging in a form of inter-state violence that, in Europe, had not been seen in decades.

Building on the analyses provided by Williams and Neumann as well as Webber and Sperling, we argue that a security community logic was central to the ways in which NATO responded to the Russian invasion of Ukraine. To begin with, from the start the Alliance interpreted the aggression as not only in terms of geostrategic confrontation but, more importantly, as a threat to the norms of the security community, and to the principles of rules-based international order promoted by the community. In this context, in the discourse articulated by NATO following the 2022 invasion of Ukraine, Russia was cast as not simply a state in search of greater material power as part of an act of balancing against the West, but, rather, as the actor that seeks to undermine the core values of the security community. This helps to explain why allies felt compelled to respond in a prompt, decisive manner—reprioritizing deterrence and defence—despite the fact that no NATO member had been attacked (or was in danger of imminent attack) by Moscow. A constructivist lens invites a socially and politically grounded account of deterrence, one which teases out its implications from the point of view of discourse and practice, as NATO and Russia redefined their intersubjective reality as rivalry rather than partnership. ³¹

This definition of threat/enemy appeared consistently both in the discourses articulated by NATO, and in the statements issued by key member states since the invasion. Consider, for instance, Stoltenberg's insistence that, in the face of Moscow's aggression—coupled with Beijing's refusal to condemn Putin's violation of the core principles of international law—it is particularly important to “stand together to protect our values.” ³² Similarly, senior NATO officials have stressed that this conflict is likely to last, as it involves a clash between the liberal-democratic values and norms defended by the transatlantic community and the illiberal ideas and practices promoted by Russia with the support of other authoritarian states. That view echoes the statements issued by leaders of NATO member states on the war in Ukraine. One of the most powerful expressions of that discourse can be found in the speech given by US president Joe Biden during a visit to Poland in March 2022. In his words:

Now in the perennial struggle for democracy and freedom, Ukraine and its people are in the front lines, fighting to save their nation and their brave resistance is part of a larger fight for essential democratic principles that unite all free people…. Today, Russia has strangled democracy and sought to do so elsewhere, not only in its homeland. There's simply no justification or provocation for Russia's choice of war. …It's nothing less than a direct challenge to the rule-based international order established since the end of World War II. And it threatens to return to decades of war that ravaged Europe before the international rule-based order was put in place. ³³

The same ideas were at the heart of the speech given by President Biden in Vilnius, following the NATO Summit of July 2023:

When Putin, and his craven lust for land and power, unleashed his brutal war on Ukraine, he was betting NATO would break apart. But he thought wrong. Faced with a threat—(applause)—faced with a threat to the peace and stability of the world, to democratic values we hold dear, to freedom itself, we did what we always do: The United States stepped up. NATO stepped up… We will not waver… Our commitment to Ukraine will not weaken. We will stand for liberty and freedom today, tomorrow, and for as long as it takes. ³⁴

Similar to Biden's discourse, the North Atlantic Council (NAC) has repeatedly characterized the war waged by Moscow as a dangerous contestation of the most important rules of international order. The war, the argument goes, is “a grave violation of international law, including the UN Charter,” and wholly contradictory to Russia's commitments in the Helsinki Final Act, the Charter of Paris, the Budapest Memorandum, and the NATO-Russia Founding Act. It constitutes an act of aggression against an independent peaceful country.” In this context, the allies “stand with the people of Ukraine and its legitimate, democratically elected president, parliament, and government.” ³⁵

In the NAC's discourse, there is a clear political and moral hierarchy, involving a sharp divide between the law-abiding, democratic NATO allies and the actor that chose to violate all norms of international society and, in so doing, generated a situation of instability in the Euro-Atlantic area. In the Council's statement issued on February 24: “We have repeatedly invited Russia to talks in the NATO-Russia Council. Russia has still not reciprocated. It is Russia, and Russia alone, which has chosen escalation…. Russia's actions pose a serious threat to Euro-Atlantic security, and they will have geo-strategic consequences.” ³⁶ In the Alliance's eyes, Russia has definitively rejected the normative underpinnings of NATO-Russia collaboration and has repudiated the most fundamental values of the modern international order. It is easy to understand how, from this perspective, no compromise or sign of weakness vis-à-vis Moscow would be acceptable.

In a broader perspective, it is interesting to stress that this crisis has demonstrated that for NATO and Russia, there were no mutually held expectations that disputes could be peacefully resolved through consultation and dialogue. Understanding how these mutual expectations are shaped, we argue, is at the heart of understanding the present war. Indeed, if one pays attention to the Russian discourse—both vis-à-vis international audiences and to its own public, it is interesting to note the reversal of the moral hierarchy portrayed by NATO—and, on this basis, a deep distrust of the Alliance and all other Western institutions. Based on Putin's imperialist reading of Russia as a great power whose “legitimate” sphere of influence (or “buffer”) is endangered by the West, Moscow depicts NATO as an existential “enemy,” and as the kind of untrustworthy actor with which no cooperation or compromise is acceptable.

It is worth noting that Putin has consistently cast its actions against Ukraine as vital to the protection of Russia and the promotion of an international order acceptable to Moscow. In a much-cited essay published in July 2021, on “the historical unity of Russians and Ukrainians,” Putin argued that Russians and Ukrainians, along with Belarusians, are one people. ³⁷ To support this claim, he put forward a narrative filled with references to the glory of the Russian Empire and described in length his views on the history of Russia and Ukraine, concluding that Russians and Ukrainians share a common heritage and destiny. Contrary to the principles of the UN Charter and basic rules of contemporary international law, Putin denied the existence of Ukraine as an independent nation and openly questioned the legitimacy of Ukraine's current borders. As he put it, modern-day Ukraine occupies historically Russian lands, and is an “anti-Russia project” created by external forces since the seventeenth century, and via administrative and political decisions made during the Soviet Union. Further, the Russian president compared “the formation of an ethnically pure Ukrainian state, aggressive towards Russia” to a use of weapons of mass destruction against Russians. It is on the basis of this narrative that President Putin justified the invasion of Ukraine in his addresses to the Russian public, and to publics in non-Western states in 2022. Depicting the conflict as one between an immoral West and a Russia seeking to protect its foundational values and its people, Putin sought to gain support for the invasion by arguing: “For our country, it is a matter of life and death, a matter of our historical future as a nation. …It is not only a very real threat to our interests but to the very existence of our state and to its sovereignty.” ³⁸

This view of NATO has meant that Russian leaders have so far rejected meaningful peace discussions not just with Ukraine but also with the West. Recently, senior Russian officials have gone so far as to claim that Moscow is fighting not just Ukraine but also an “arrogant” West—represented by NATO—which has “sown chaos” in the world and is now keen on wiping Russia off the map. ³⁹ In essence, the differences between NATO and Russia are seen by both parties as irreconcilable.

Returning to NATO, it is also interesting to note that, consistent with the security community logic, its senior officials have repeatedly cast its relationship vis-à-vis Ukraine in terms of partnership in support of a particular (democratic) set of values and institutions, seen as key to Euro-Atlantic security. Thus, in the official NATO discourse, “A sovereign, independent and stable Ukraine, firmly committed to democracy and the rule of law, is key to Euro-Atlantic security.” ⁴⁰ That discourse has been systematically and very visibly embraced by the Ukrainian political leadership, especially by President Volodymyr Zelensky, who has framed Ukraine as a defender of the values of the transatlantic community to cast Ukraine's war as part of the defining conflict between liberal democracy and its existential enemies. On this logic, the conflict between Ukraine and Russia is no less that the confrontation between Europe's dangerous, violent past (represented by Moscow's violent actions) and the stable, prosperous future promoted by the liberal-democratic world. By embracing this vision and skillfully mobilizing social media, President Zelensky has effectively appealed not only to NATO and to allied governments but also to the allied publics. His explicit aim has been to shame everyone into more support for Ukraine, and to delegitimize inaction or timid action by NATO allies, casting such actions as inconsistent with the values of democracy and freedom around which the West defines itself. ⁴¹

This threat discourse ultimately shaped powerfully the ways in which the Alliance responded to the war. Summarizing the Alliance's position at the April 2022 Foreign Ministers Summit, Secretary General Stoltenberg stated: “We agreed that we must further strengthen and sustain our support to Ukraine. So that Ukraine prevails in the face of Russia's invasion.” ⁴² As he reminded global audiences,

NATO Allies and NATO have supported Ukraine for many years. After the illegal annexation of Crimea and Russia's first invasion in 2014, also into Donbas, NATO Allies and NATO have provided significant support with equipment, with training tens of thousands of Ukrainian soldiers and then when we saw the intelligence indicating a highly likely invasion Allies stepped up last autumn and this winter. Then after the invasion, Allies have stepped up with additional military support, with more military equipment. ⁴³

This includes lethal equipment to be used against Russia, despite Moscow's threats that such assistance could be seen as a hostile act and could trigger retaliation.

In a situation in which Russia is seen as posing an existential threat to the rules-bases international order supported by the security community, the allies’ retaliation has been not only surprisingly swift and coherent, but also unusually comprehensive. Following a multi-faceted international approach jointly supported by the EU and NATO, Russia, as we have seen, came to be subjected to “unprecedented” sanctions affecting virtually all aspects of its economy and society. Further, the mobilization of the security community in response to a perceived threat to its core values has transcended the domain of governmental actors, embracing a “whole-of-society” approach in which all members of the transatlantic security community are expected to support the war against Moscow, as proof of their support for the core values of the community. This was most apparent as international businesses shut down their activities in Russia and even offered direct support for Ukraine, as demonstrated by the social media companies whose support in the information domain has been significant.

The logic of security community protection has also been at play in shaping the Alliance's response to the partners seen as vulnerable to Moscow's hostile actions, such as those from the Western Balkans and former Soviet Union. In particular, the package of measures adopted by NATO in support of those allies includes aid aimed at strengthening the resilience of their democratic societies, based on the assumption—inspired by the security community logic—that stable democratic neighbors are an asset for the stability of NATO allies. ⁴⁴ To take just one example, consider NATO's approach to the Republic of Moldova. At the 2022 NATO Summit, the allies agreed on a package of tailored support measures to help Moldova strengthen its national resilience and civil preparedness. The Enhanced Package was subsequently endorsed by NATO defence ministers at their February 2023 meeting. That package seeks to support Moldova in implementing its own long-term development and modernization plans for security and defence. It will further support Moldova in strengthening its training and logistics capacity, human resources management, cyber defence, and strategic communications. Furthermore, through the Defence Education Enhancement Programme (DEEP), NATO provides advice on how to build, develop, and reform educational institutions to help Moldova build a professional military education system, with university degrees and specialized courses offered by Moldova's Military Academy, its Continuous Training Centre, and the Non-Commissioned Officers School. In addition, through the Building Integrity programme, NATO provides Moldova with strategic-level advice on strengthening good governance and reducing the risk of corruption, particularly in its defence and security sector. ⁴⁵ This investment in capacity building, rather than material resources alone, is further evidence that the security community logic is at play, as it ties security and defence improvements to NATO standards and best practices.

Normative dilemmas and challenges

While the mobilization of NATO allies gained rapid momentum following the Russian aggression of Ukraine, it would be naive to assume that this marks the end of all intra-alliance tensions, challenges, and normative dilemmas facing the security community. For allied leaders, the challenge now is to find ways to sustain that momentum and unity over the long term. This point was emphasised by US president Joe Biden, who argued: “We must commit now to be in this fight for the long haul. We must remain unified today and tomorrow and the day after. And for the years and decades to come.” ⁴⁶ To achieve the goal of unity in the long term, NATO allies and their partners must overcome declining trust, persisting political polarization, shifting economic burdens, and the complexities associated with redefining collective defence in a changing, multi-domain security environment.

One of the most serious challenges facing the security community concerns the deficit of trust among its members. As constructivist scholars stress, a key condition for developing and maintaining a security community is the establishment and maintenance of trust among its members. This social phenomenon depends on the community's assessment that each actor will behave in ways consistent with the group's normative expectations. ⁴⁷ Yet, in recent years, key allies have behaved in ways that are inconsistent with normative expectations within NATO, thereby undermining the trust that underpins the security community. The political ascendancy of populist and illiberal forces in the transatlantic area, like the rise of “Trumpism” in the US or Victor Orbán's so-called illiberal model of democracy, has created deep strains within NATO. For example, former President Trump consistently and openly violated key norms of the security community, attacking norms of dialogue, consultation, and multilateral cooperation, questioning the value of NATO, and systematically undermining liberal values such as the rule of law and respect for individual rights—both at home and abroad. ⁴⁸

While President Biden's explicit support for multilateralism in general and NATO in particular has marked a significant, highly positive change from the Trump era, there is a persistent fear that Trumpist ideas will remain part of the American political landscape. The ongoing reluctance, in some Republican circles, to adopt a clear stance against Russia and in support of NATO in the context of the Ukraine war reinforces that fear. Recent public opinion polls, in addition to a vote in the US Congress, suggest that Republican support for NATO was undermined significantly with the arrival of Trump on the scene. Indeed, 30 percent of House Republicans withheld their support from a resolution which sought to reaffirm American backing for NATO, a break with the past bipartisan consensus NATO enjoyed in the US Congress. ⁴⁹ It is worth recalling that Trump has consistently signaled his disdain for NATO, at one time calling the Alliance “obsolete” ⁵⁰ and appearing friendlier to Putin than to Angela Merkel while president. Still, Trump's record on NATO is not entirely grim, as he held the course on thickening the Eastern flank, with Poland as the key partner in this regard.

Furthermore, even President Biden's record has not been impeccable. In fact, his administration's failure to consult with allies before withdrawing US forces from Afghanistan, and the chaotic manner in which the US withdrawal was conducted, again dealt a massive blow to US credibility in the eyes of its allies, and raised new questions about Washington's commitment to the norms of the security community. ⁵¹ The declining trust in the US has already had tangible consequences in the context of the Ukraine crisis—as seen, for instance, in the reluctance of certain allies, like France, to trust American intelligence reports about Putin's plans to launch a massive invasion of Ukraine. NATO's ability to recover quickly and plan a coordinated response efficiently is a testament to its tight web of institutionalized cooperation, which allows allies to resolve differences peacefully and makes it possible for intra-alliance relationships to bounce back after strain.

Despite the resilience demonstrated so far, however, it would be naive to assume that the Alliance has definitively transcended challenges to its unity. In fact, there are reasons to believe that NATO will face serious difficulties in the coming years. Particularly worrisome is the persistent and, in some instances, growing power of the above-mentioned illiberal political forces in several member states. As noted earlier, the most dangerous developments concern the persistence of Trumpism in the US, and the real possibility that Trump himself (or someone with similar ideas) may return to power following the next American elections. But the US is certainly not the only problematic ally in this respect. Consider, for instance, recent developments in Turkey, where an increasingly authoritarian President Recep Tayyip Erdoğan took military cooperation with Russia to unprecedented levels, raising doubts about Ankara's willingness to confront Moscow. ⁵² More recently, it complicated NATO's response to the war and generated inter-allied frictions by delaying the accession of Sweden to the Alliance. ⁵³ In Hungary, Prime Minister Orbán has already opposed important aspects of NATO cooperation with Ukraine. His recent re-election, openly celebrated by President Putin, and the fact that Orbán used his victory speech to criticize Ukraine's President Zelensky, triggered concern among allied politicians, who fear that Budapest may not be a reliable, trustworthy partner in the coming years. ⁵⁴ Orbán's actions have proven so concerning that they have even been countered by punitive measures within the EU setting. ⁵⁵ These trends signal that the expectation among NATO members that disputes and disagreements will be resolved through consultation has already been considerably weakened. Still, a constructivist logic does not predict the absence of disagreements within security communities, but expects shared norms to shape reactions, leading to a situation where institutional channels are privileged, with incremental and measured responses to perceived transgressions.

So far, as we have seen, the allies have been able to resolve or at least cope with differences and maintain a reasonable degree of cohesion within the security community. The danger, though, is that in the future, the growing power of illiberal forces in key allied states may translate into even more systemic attacks on shared norms and institutional channels. This, in turn, would increase the trust deficit, making it increasingly difficult for members of the security community to adapt to changing circumstances and agree on appropriate responses to various challenges and potential threats.

The trust deficit presents risks to NATO unity, and has deeper implications for collective defence, a term which is at once fundamental to NATO's identity and in the process of being reinvented. The insight we can draw from constructivism on this question draws our attention to how a concept like collective defence takes on meanings that then shape diplomatic and military practices. More concretely, in a complex security environment, NATO's increasingly adversarial relationship with Russia over the last decade has broadened the lens through which the Alliance conceives of deterrence and defence. As noted above, NATO conceptualizes the challenge posed by Russia not simply as a military threat but, more broadly, as a multi-faceted attempt to undermine the core liberal-democratic values and institutions of the transatlantic community. In this context, the allies have expressed concern about—and determination to ensure effective collective defence from— multi-dimensional, multi-domain (or hybrid) attacks. Starting from the recognition that the contemporary security environment is unpredictable, at the 2016 Summit in Warsaw, allied leaders decided to boost NATO's “resilience to the full spectrum of threats.” ⁵⁶

What has emerged in response to the rise of hybrid tactics by near-peer competitors is the broadening of traditional military domains, to include cyber, space, and information. Defining collective defence in a multi-domain security environment, then, is emerging as a strategic and operational challenge, but one where military adaptation has probably outpaced political thinking. ⁵⁷ Indeed, this ambiguity is plainly visible in the way NATO has identified cyberattacks as being covered by Article 5 provisions, yet the threshold for determining when and how to respond to such attacks seems to be a perennial point of contention. ⁵⁸ Therefore, this process of reinvention or, dare we say, cognitive evolution also creates ambiguity which can make it harder for allies to consult and take action on challenges which require a collective defence response.

The trust deficit has also bled into other issues within NATO, like burden-sharing. ⁵⁹ The massive asymmetry between US spending and the resources devoted to defence in other allied states has long been the topic of difficult conversations in the NAC, though allies have boosted their defence spending in response to Russia's annexation of Crimea in 2014 and, more forcefully, with the full-blown war in 2022. The most spectacular change came from the German government's decision to meet the 2 percent GDP commitment in 2022 and to create a fund of 100 billion EUR dedicated to defence investment. Other significant moves include major increases to defence spending by countries of the former Warsaw Pact, including Poland and the Baltic states. Still, it is unclear if the new focus on defence spending in several allied states means that the allies can be trusted to agree on collective defence priorities and work together towards translating this into a coherent, substantial European contribution to NATO. ⁶⁰ There are also questions about the types of capabilities that member states will develop or acquire, the ways in which such capabilities may be used once acquired, and the institutional frameworks that will govern European defence policies in support of the EU Strategic Compass.

Finally, the security community faces complex questions in (re)defining relations with partners in the new security environment. Partnership building has long been central to the security community logic, embodying the “disposition towards spreading the community outward through explicit or implicit practices of socialisation or teaching.” ⁶¹ Yet, it is not clear what the Alliance representing the security community should do to protect its partners in situations of conflict. In this area, it is hard to avoid complex normative dilemmas—which have proven especially difficult to navigate as NATO members have continuously increased the scope of their assistance to Ukraine following the Russian invasion. Speaking on behalf of the Alliance, Secretary General Stoltenberg explicitly stated that: “NATO Allies provide support to Ukraine, [but] at the same time, NATO's main responsibility is to protect and defend all Allies, and to prevent this conflict from escalating to full-fledged war between NATO and Russia.” ⁶²

That balancing act is painful to sustain when presented with evidence of war crimes and potential acts of genocide committed by Russian forces in Ukraine. In particular, the international legal obligations deriving from the Genocide Convention, and the fact that several leaders of allied states, including President Biden, have accused Russia of genocide, would suggest that NATO states have a duty to take more forceful action in support of Ukraine. ⁶³ It is important to note that the Convention on the Prevention and Punishment of the Crime of Genocide (CPPCG), or the Genocide Convention, which entered into force in 1951, criminalizes genocide and obligates state parties to enforce its prohibition. In the absence of stronger action to enforce the prohibition imposed by the Genocide Convention, the credibility of NATO as the institution of a community of liberal-democratic values could be severely undermined—in the eyes of its partners, its publics, and, more broadly, the international community. Yet, it is difficult to see how the Alliance could act in a more forceful way without significantly increasing the risk of (potentially nuclear) confrontation with Russia—which would have devastating consequences both for the security community and its partners.

Conclusion

Over the span of two decades, President Putin's actions have downgraded Russia's relationship with NATO from a constructive partnership to one of open enmity. Over most of this period, Russia became economically and militarily stronger; all the while, NATO's collective defence spending was on a downward trend, until Putin's decision to annex Crimea reversed it. In the final analysis, Russia rejected the normative underpinnings of NATO-Russia collaboration. For NATO and Russia, when disagreements emerged over enlargement, partnerships, cooperative security, and policies vis-à-vis Ukraine, there were no mutually held expectations that disputes could be peacefully resolved through consultation and dialogue. Understanding how those mutual expectations were shaped and how they were connected to broader interpretations of self/other, we argue, is central to understanding the present war.

While the Russia-NATO partnership suffered a serious blow after the annexation of Crimea, when Russia was “re-securitized” by the Alliance, the crisis was taken to new levels following the full-scale invasion of Ukraine in 2022. That invasion led to a significant revitalization of NATO, which embarked on an unprecedented campaign to support Kyiv in its confrontation with Russia.

The level of support provided by NATO, as well as the level of mobilization against Moscow is particularly interesting in a situation in which none of the Allies were either attacked or in danger of imminent attack. Indeed, one could argue that if geo-strategic considerations alone had prevailed, NATO members could have interpreted the crisis as a regional conflict outside of its area of interest—and, furthermore, as proof that NATO's deterrence was effective and did not need radical changes or upgrades. In this context, we have argued in this article that, in order to understand NATO's actions vis-à-vis both Russia and Ukraine, it is useful to draw on the constructivist logic of security communities. Doing so has enabled us to show how actions taken in the name of collective defence have in effect amounted to an effort to protect not just the allied territory and populations but, more broadly, the norms and values of the security community that NATO claims to embody. The Allied discourse on the war in Ukraine as representing a contestation between the democratic values of the security community and the dangerous principles of authoritarian governance has translated into a series of ambitious, expensive measures in support of Ukraine and other vulnerable states from the former communist bloc that would have been hard to justify if the Allies had focused exclusively on narrow geo-strategic considerations related to Article 5.

Our aim in this article was not to pit our analysis against realism per se. Rather, we highlighted the limits of influential structural realist arguments that emerged as dominant in many academic circles in recent years, and sought to demonstrate how an analysis grounded in constructivist thinking about security communities can offer a more complete reading of why and how allies have responded to Russian aggression against Ukraine in 2014 and 2022. Indeed, while we have found the security community literature particularly helpful, we note that some realist thinking of the classical and neoclassical variants might also establish a connection between values and interests, as well as intra-alliance versus external factors. A broader analysis of regional security is beyond the scope of this paper, but we suggest that, in future research, a dialogue between constructivism and classical/neo-classical realism could lead to a fruitful and nuanced debate on the future of NATO in a more contested regional security context. ⁶⁴

More immediately: a constructivist reading of the current situation also enables us to study NATO's own internal dynamics more closely. Bigger challenges to NATO's internal politics may lie ahead, however, as the return of a norm saboteur like Trump could severely undermine the terms and meaning of the transatlantic bargain. To this end, we identified challenges to NATO unity and trust, its perennial burden-sharing problems, and the difficulty of redefining collective defence in the context of a dynamic and volatile security environment. Understanding the social interactions that define NATO's internal politics and external relationships constitutes a significant contribution to analyses of an institution commonly referred to as the most successful alliance in history and, in a broader perspective, to knowledge about the evolution of the field of security in the twenty-first century.