South Korea and NATO: from unlikely companions to key partners


 Relations between South Korea and NATO have been deepening at a striking pace recently. Yoon Suk Yeol became the first South Korean president to attend a NATO Summit in 2022 and in the same year, Seoul opened its diplomatic mission to NATO in Brussels. South Korea also became the first east Asian country to join a NATO Centre of Excellence, and started increased consultations with NATO's military staffs. There is a gap in the literature on South Korea–NATO relations which this article aims to fill as it examines the reasons behind the rapidly deepening relations between South Korea and NATO in recent years. To understand the dynamics that triggered the rapid development of South Korea–NATO relations, this article applies Bence Nemeth's theory on defence cooperation which focuses on the interplay of three structural and two situational factors. We argue that the constellation of these factors operating together led the two sides to deepen cooperation organically over almost two decades. Path-dependent processes accrued through prior experiences of collaboration and institutional ‘stickiness’, aided by the positive rapport between leaders in office, allowed the two sides to deepen cooperation when the external environment required it following Russia's invasion of Ukraine.

It might not be immediately apparent why a robust security partnership between South Korea and NATO could emerge, as they exist in very different geographical regions.Still, in January 2023, South Korean President Yoon Suk Yeol hosted NATO Secretary-General Jens Stoltenberg in Seoul, where he highlighted that South Korea-NATO relations have recently deepened rapidly. 1 Indeed, the period since February 2022, when the Russian invasion of Ukraine began, has witnessed a clear alignment between the policies adopted by South Korea and by NATO members.Notably, South Korea sided with the West in condemning Russia's actions, implementing sanctions against the Russian regime and sending financial and material support to Ukraine.
President Yoon also attended the NATO summits in Madrid in 2022 and Vilnius in 2023, becoming the first South Korean head of state to attend a meeting of the alliance's heads of state and government.In 2022, the South Korean government opened a diplomatic mission to NATO in Brussels to coordinate its policies with the alliance.In the same year, South Korea became the first east Asian country to join a NATO Centre of Excellence by sending cyber experts from its national intelligence service to participate in the work of the NATO's Cooperative Cyber Defence Centre of Excellence (CCDCOE), 2 located in Tallinn, Estonia.Consultations started to take place regularly between the military staffs of NATO and South Korea on a wide range of topics, including the participation in NATO military exercises of South Korean troops. 3South Korea and NATO also adopted the Individually Tailored Partnership Programme in 2023, which covers bilateral cooperation in sectors including cyber security, disarmament and nonproliferation. 4 International Affairs 100: 2, 2024 Some of these developments are not unique to South Korea, and they took place in the context of NATO's wider outreach towards its Asia-Pacific partners-Australia, Japan and New Zealand, in addition to South Korea-after Russia's invasion of Ukraine.However, what differentiates South Korea's relations with NATO is the speed with which close relations have developed in the most recent period.While South Korea used to lag behind other countries in deepening its collaborations with NATO, it has now caught up with NATO's other Asia-Pacific partners and is even at the forefront in certain aspects.
South Korea has been cooperating with NATO for almost two decades, but relations between the two sides have been deepening at a markedly quicker pace for the past few years.This article attempts to answer a two-part question-namely, why is this happening, and why is it happening now?In a broader sense, we are interested in why specific actors in international affairs might start to cooperate and deepen their relationship.To answer these questions, first we introduce the theoretical framework that helps to explain the genesis of defence collaborations, which we subsequently apply to the South Korea-NATO case.The following five sections examine the factors (both structural and situational) that prompted the deepening of collaboration between South Korea and NATO.The final section concludes the article with a discussion of the wider policy and conceptual implications, focusing on how the relevant factors interacted to shape the trajectory of South Korea-NATO relations particularly since Russia's invasion of Ukraine in 2022.

Achieving defence cooperation
Security and defence cooperation among partners and allies is commonplace in international affairs, and alliance politics has an extremely rich academic and policy literature. 5However, not every instance of security and defence cooperation is necessarily based on formal alliances.For example, mutual defence treaties underpin relations between members of NATO and also between the US and Japan.At the same time, some observers argue that China and Russia are very close strategic partners, while others perceive their relationship as an alliance even though there is no document formalizing it as such. 6However, no-one claims that South Korea-NATO relations would constitute an alliance.Accordingly, concepts originating from the literature on alliances that traditionally explain alliance politics such as abandonment or entrapment7 are less helpful in understanding South Korea-NATO relations.
Scholars have extensively discussed security cooperation which cannot be explained by theories related to alliances.For instance, Victor Cha terms such security collaborations as quasi-alliances 'in which two states remain unallied but International Affairs 100: 2, 2024 share a third party as a common ally'. 8This approach is relevant to NATO-South Korea relations, since the United States participates in both NATO and the bilateral South Korea-US alliance.However, this concept does not help to explain why NATO and South Korea started to deepen their relations only recently, after sharing the same ally (the US) for more than seven decades.Another widely studied subject is alignments between states.Although the expressions of 'alignment' and 'alliances' are often used interchangeably in the scholarship, alignment has grown into a distinct subject of study.For instance, Glenn Snyder defines alignment as 'expectations of states about whether they will be supported or opposed by other states in future interactions'. 9Building on his concept, scholars have studied several aspects of international security cooperation. 10Indeed, one might argue that NATO and South Korea have been in alignment for a long time, ever since South Korea contributed a detachment of 210 medical and engineering troops to NATO's International Security Assistance Force (ISAF) mission to Afghanistan in 2002.However, alignment-related concepts are less useful in providing insights as to why a step change might occur in the quality of a security cooperation.Thus, theoretical frameworks that shed light on the origins of security cooperation or the acceleration of such cooperation are more relevant to answer our two-part research question: what underpins the rapid improvement in NATO-South Korea security cooperation over recent years, and why is this improvement happening now?
To answer this question, our article utilizes Bence Nemeth's theory on defence cooperation, which concentrates on the interplay of three structural and two situational factors relevant to establishing new defence collaborations. 11Nemeth's theory was originally developed to understand the factors necessary to launch new bi-and minilateral defence cooperations in Europe, and focuses explicitly on the genesis of defence collaborations.Accordingly, it is a useful theoretical tool that can reveal the dynamics of the swiftly deepening security cooperation and new initiatives that have been recently established between South Korea and NATO.At the same time, as the theory was designed to explain defence collaborations in Europe, we slightly modify it for the purposes of our article, making it applicable outside Europe and to wider security collaborations, instead of its original narrower defence focus.
By applying Nemeth's modified theory to the South Korea-NATO case, we argue that the rapid development of relations between South Korea and NATO is not the result of the war in Ukraine per se.Furthermore, it was not established in a top-down manner, but sprouted from multiple branches across various subfields of cooperation and levels of office.In other words, the constellation of multiple International Affairs 100: 2, 2024 factors operating together led the two sides to deepen cooperation organically over the course of almost two decades.Path dependent processes accrued through prior experiences of collaboration and institutional 'stickiness' allowed the two sides to rapidly deepen cooperation when the external environment required it following Russia's invasion of Ukraine.
One of Nemeth's key arguments is that when a new security collaboration is established, we should focus on the relevant policy communities of the countries involved as the unit of analysis, instead of the states themselves.The concept of policy community is well established in policy studies and has been widely used since the 1970s. 12For instance, Grant Jordan defines the concept of policy community thus: Policy community refers to the population of organizations with a stake in an area of public policy.In its more technical sense, it refers to interorganizational structures exhibiting a close, stable, cooperative relationship between a limited number of, mainly self-selected, interest groups and 'partnering' elements of the governmental machinery. 13sed on this logic, we are building on Nemeth's interpretation and define the security policy community (SPC) of a country as the 'network of groups and people who have the expertise, will and opportunity to influence' the security policy of a state, as they also have the most significant influence in establishing security collaborations. 14lthough South Korea-NATO relations have relevant military elements, their cooperation is also political and goes beyond purely military aspects of security to include issues such as 'non-proliferation, cyber defence, science and technology, counter-terrorism, interoperability, and defence against chemical, biological, radiological and nuclear (CBRN) agents'. 15Accordingly, in terms of South Korea, the SPC regarding NATO relations includes several actors like members of the presidential administration, certain members of the General Assembly, groups in the Ministry of Foreign Affairs, the Ministry of National Defense, the National Intelligence Service, the South Korean defence industry and the think tank/ scholarly community.From NATO's perspective, this is more complicated.First, NATO is a political-military alliance of 31 member states from North America and Europe, and each of them has veto power over decisions in the NATO alliance.Second, NATO has its own institutions, command structure and agencies, where about 10,000 civilian and military personnel work.The face of the alliance is the NATO Secretary-General, the top international civil servant of the organization, who chairs the meetings of the North Atlantic Council-NATO's main political decision-making body-and is also the organization's spokesperson.The dynamics between NATO members influence policy decisions, while NATO International Affairs 100: 2, 2024 as an organization also shapes the agenda and is responsible for implementing certain decisions made by alliance members.Thus, the members of the SPC of NATO come partially from the SPCs of NATO member states and partially from NATO's own organizational elements.
Based on Nemeth's theoretical framework, we will analyse the interplay of three structural and two situational factors, which-according to this theory-are necessary to launch a new security cooperation between SPCs.Structural factors are those longstanding trends, perceptions, relationships and institutions that develop over a longer period of time.They do not trigger defence collaborations, but 'they enable them and provide the conditions for their creation'. 16Situational factors are relatively quickly changing political, economic and personal constellations that trigger the launch of security cooperation and can explain why a collaboration was established at a particular time. 17he first structural factor we consider here is the de facto security community between South Korea and NATO.On the fundamental level, a security community is a group of states which do not expect to use military force against each other to resolve their conflicts.Usually, these states share norms and values, and have a sense of community. 18The existence of the security community is crucial for establishing security collaborations, as without this element, members of an SPC would not trust each other enough to cooperate on security issues in a meaningful way.NATO members and South Korea are formal allies of the United States, which provides the basis for creating a sense of community between NATO and South Korea.Furthermore, NATO is widely seen as a security community which fosters collaboration with members and partners through institutional processes.According to Emanuel Adler, 'by offering security and economic partnerships, the community's multilateral institutions entice and teach partners to adopt the community's core standards and practices'. 19South Korea has engaged and cooperated with NATO for almost two decades and has learned some of its processes and standards over this period.
The second structural factor is the perception of a lack of resources by the SPCs of South Korea and NATO.In general, many security collaborations start-at least in part-because the different parties believe that they lack certain resources to achieve their goals, and hope that by cooperating with partners the problems associated with a lack of resources could be mitigated.For instance, in European bi-and minilateral defence cooperation, the lack of financial resources plays a crucial role. 20Lacking resources might also mean lacking expertise in certain areas, or political legitimacy, or political support, and so on.As we will see, NATO has been deepening its collaborations with partners from different International Affairs 100: 2, 2024 regions to increase its legitimacy and capacities.At the same time, South Korea has traditionally focused on security issues on the Korean peninsula.As a result, it has not paid sufficient attention to joining mini-or multilateral forums, where it could represent its interests.This has generated significant problems for the South Korean SPC.
The third structural factor is previous collaborations.Nemeth points out that most 'new' security cooperations are not entirely new.Usually, they build on previous collaborations and are often path dependent, because it is easier to cooperate with an existing partner, with which a state has established personal and institutional relations, than with a totally new partner.Thus, replacing a security collaboration always carries higher opportunity costs than building on a previous one. 21As mentioned earlier, South Korea-NATO relations go back almost two decades, and South Korean troops contributed significant forces to NATO's ISAF mission to Afghanistan.
Structural factors enable launching of new security collaborations, but situational factors trigger them.The first situational factor is strong leadership by a group of high-level officials and good interpersonal chemistry between them.This is important because without actual people nothing happens, and starting a new cooperative initiative usually requires significant extra effort.Thus, high-level officials in the right places need to work closely together across different SPCs and put extra effort into making the new initiative work.However, they will likely face resistance from various stakeholders, and in order to overcome these difficulties, key leaders need to show strong leadership.If they have positive interpersonal chemistry and like each other, they are likely to put in the extra effort to overcome difficulties and win over stakeholders.The relationship between South Korean President Yoon and US President Biden is crucial in our case.
The second situational factor is a supportive political milieu.Even if every structural factor is aligned and high-level leaders from different SPCs demonstrate strong leadership and have interpersonal 'chemistry', they would work in a vacuum-and would have less chance of gaining support from their SPC and other stakeholders-without a supportive political environment.The latter is always time and context-specific and provides a window of opportunity to successfully begin a cooperation.
These factors interact on two levels, and in a particular way.On the first level, the security community provides the trust, values and sense of community as an umbrella and prerequisite for cooperation.On the second level, previous defence collaborations and the perception of a lack of resources create options for enduring collaborations in the future.However, security collaboration will only be realized if the situational factors of the right personal relationships and a supportive political milieu are aligned.At the same time, interactions on the second level also affect the first level, strengthening or weakening the trust in the security community.

Structural factor 1: a de facto security community
The existence of a security community between South Korea and NATO is a prerequisite for meaningful bilateral security cooperation.Karl Deutsch defines a security community as a group where there is 'real assurance that the members of that community will not fight each other physically, but will settle their disputes in some other way', so much so that there is 'dependable expectations of "peaceful change"'. 22This definition qualifies South Korea and NATO to constitute a security community.
The foundation of this security community is that South Korea, the European NATO members and Canada all enjoy US security guarantees.NATO members pledged in 1949 'that an armed attack against one or more of them in Europe or North America shall be considered an attack against them all' 23 and the US provides the bulk of military capabilities in the alliance.Over the last three decades, NATO members have worked closely together under US leadership in several military conflicts in the Balkans, in Afghanistan and in Libya, demonstrating their strong bonds.At the same time, the US and South Korea have a mutual defence agreement and American troops have been permanently stationed in South Korea since the Korean War (1950-53).Furthermore, in 1989, South Korea was among the first batch of countries to be designated by the US government as 'major non-NATO allies'. 24South Korea has supported the US in every major conflict where the latter has been involved since the Vietnam War.Thus, both NATO 25 and the US-South Korea alliance 26 are depicted by scholars as security communities.
Thus, the sense that South Korea and NATO are reassured that they will not fight each other and their disputes will definitely be settled peacefully stems from the fact that they share the same ally, the US.It could be argued, however, that it is not the degree of integration which prevents an armed conflict between South Korea and NATO like in the case of the European security community.There could be other factors, such as the lack of points of contention or geographic distance.In other words, a lack of armed conflict between two parties might not necessarily reflect the existence of a security community.
However, a dozen NATO members fought in support of South Korea in the Korean War.Currently, six NATO members contribute military personnel to the United Nations Command (UNC), the multinational military force which has been supporting South Korea during and after the Korean War.The United States provides the vast majority of the troops, while Canada, Denmark, France, Greece and the United Kingdom also contribute military personnel. 27The commander of International Affairs 100: 2, 2024 the UNC is always an American four-star general, while the current and previous deputy commanders have come from other NATO members, Canada and the United Kingdom respectively.At the same time, South Korea has contributed significant aid and personnel to NATO missions, including leading a provincial reconstruction team of 470 civilian and military personnel deployed to Afghanistan's Parwan province between 2010 and 2013.NATO forces have also collaborated with the Republic of Korea Navy (South Korea's naval force) to counter piracy in the Gulf of Aden. 28till, it is awkward to speak of an idea of 'we-ness' between NATO and South Korea, and of a similar expectation of altruism as exists in the case of the European security community. 29Adler and Barnett's framework, which distinguishes between loosely-and tightly-coupled security communities, can be helpful in this regard.Loosely-coupled security communities are based on shared values and identity, and 'there are multiple and diverse mechanisms and patterns of interaction that reinforce and reproduce' such communities. 30However, 'in a tightly coupled security community, mutual aid becomes a matter of habit and … thus, national identity is expressed through the merging of efforts'-which often manifests in collective security arrangements and a high degree of military integration. 31ased on Adler and Barnett's framework, South Korea does not share a tightlycoupled security community with NATO members other than the US.South Korea and NATO are mainly a loosely-coupled security community, but South Korea and the United States form a tightly-coupled security community as they have a mutual defence treaty and an extremely high level of military integration.NATO also constitutes a tightly-coupled security community with security guarantees, integrated military command structure and US leadership.
At the same time, South Korea and most NATO members form a looselycoupled security community based on shared values and identities.The relevance of shared values has been consistently reflected in speeches of South Korean and NATO officials.In 2005, South Korea's Minister of Foreign Affairs and Trade, Ban Ki-moon stated: 'Korea and NATO share common values such as democracy, respect for human rights and an aspiration for peace.' 32 This message was reiterated by other South Korean foreign ministers, including Yoon Byung-se in 2016, when he highlighted that: Recently, not only shared values but the interconnectedness between NATO's and South Korea's regions have been emphasized in different speeches.For instance, the Chair of the NATO Military Committee, Admiral Rob Bauer, pointed out in 2022 that NATO and South Korea 'are all working to serve a greater good: the protection of freedom and democracy.That task … forms an invisible bond that transcends wars, generations and even continents'. 34Meanwhile, Lieutenant General Francesco Diella, the director of NATO's Cooperative Security Division stated in 2023: NATO and Korea are strong partners … Working with like-minded partners has become even more important as transatlantic and Indo-Pacific security are deeply interconnected.What happens in Europe matters to the Indo-Pacific, and what happens in the Indo-Pacific matters to NATO. 35cordingly, not only shared values but shared security concerns and their perceived connections are more and more visible in the manifestation of the NATO-South Korea security community.Taken together, the perception of 'we-ness' through US security guarantees, shared values and security concerns, the establishment of institutional and organizational links between the South Korean and NATO SPCs are the building blocks of this loosely-coupled security community.This provides the foundation and trust for deeper collaborations between NATO and South Korea.Although this is a significant precondition, explaining why the two sides recently deepened their relations is insufficient.To delve further, it is important to assess the remaining four factors.

Structural factor 2: a perceived lack of resources
SPCs often perceive that they lack resources 'they deem necessary to have in order to maintain their social roles and answer the perceived challenges of the international environment'. 36For instance, in Europe, numerous armed forces perceived that they did not get sufficient financial resources in the period following the Cold War-which is one of the reasons why they initiated defence collaborations.Michael Alexander and Timothy Garden pointed out as early as 2001 that the financial resources of European militaries shrank so significantly due to defence budget cuts and high level of defence inflation that the 'arithmetic of defence policy' required more multinational cooperation on military capability development. 37Although European armed forces could have accepted that they lost even more structures and capabilities, they often decided to work together with other armed forces to preserve them.Thus, either explicitly or implicitly, most defence cooperation in Europe has had a financial aspect that stems from a perceived lack of financial resources by SPCs.
International Affairs 100: 2, 2024 In the case of the rapidly deepening South Korea-NATO relations since 2022, a perceived lack of resources has also played a key role, but the financial aspect was less relevant for South Korea.Instead, South Korea's lack of international forums to engage its allies and partners has become a growing issue for the South Korean SPC.Traditionally, South Korea focused primarily on the threat coming from North Korea, and-understandably-it invested its military and diplomatic resources in managing the related security issues.However, this sole focus had a price.Even though South Korea has grown into an economic, cultural and military powerhouse since the end of the Korean War, it has had limited options to engage with its main ally, the US, and other partners other than in bilateral meetings and a few international forums.For this reason, according to Zack Cooper, 'Seoul now finds itself the most under-institutionalised country [for international cooperation] out of all the advanced industrial democracies'. 38ndeed, this is not a new problem, as the South Korean SPC was aware of it.South Korea's foreign and security focus started to broaden from the late 2010s, and, initially, its governments prioritized south and south-east Asia as part of the New Southern Policy. 39However, the issue of resolving the lack of opportunities to engage with partners received a new impetus with the election of President Yoon Suk Yeol in 2022.
Yoon's main foreign policy goal was to change South Korea's North Koreafocused international approach and to make South Korea a global pivotal state, 'one that advances freedom, peace, and prosperity through liberal democratic values and substantial cooperation'. 40Thus, the South Korean SPC perceived the lack of options for international cooperation as a lack of critical resources.Since the beginning of the Yoon administration, the SPC has realized that NATO could provide a forum for this cooperation, and has exploited this opportunity well.NATO's 2022 Madrid summit was the first one in which a South Korean president participated, and President Yoon used the opportunity to repair South Korea's relations with Japan, among other purposes.On the margins of the NATO summit, Yoon participated in a trilateral meeting with President Biden and Fumio Kishida, the Prime Minister of Japan-the first such high-level meeting since 2017.This meeting helped to relaunch security cooperation between South Korea and Japan, which had for some years remained highly problematic. 41Furthermore, the South Korean SPC International Affairs 100: 2, 2024 deepened its ties with key NATO allies and partners during the NATO summit through a total of ten bilateral meetings. 42he perception of a lack of critical resources was also prevalent among the SPCs of NATO members.First, although western sanctions had harmed the Russian economy after the occupation of Crimea in 2014, their effect was limited, and they did not achieve their main goal, of convincing Russia to reverse its actions.Thus, it became clear that the sanctions implemented were neither strong nor wide-reaching enough to change Russian behaviour. 43Second, European NATO members had known military capability gaps, and their stockpiles were limited as they had not needed to prepare for a protracted war since the end of the Cold War.This was already clear during NATO's intervention in Libya in 2011, as 'several European NATO allies and partners were confronted with severe resupply and ammunition deficits', which stretched their ammunition stockpiles 'almost to their respective breaking points'. 44These structural problems were well known for a long time, but NATO members did not address them, and it only became urgent that they were managed in the context of the Russian invasion of Ukraine.
South Korea emerged as a potential major partner who could help in part to improve the effectiveness of sanctions and mitigate the problem of lack of ammunition stocks.After Russia invaded Ukraine in February 2022, western nations imposed a new series of extremely robust sanctions against Moscow and wanted others to join them to reduce Russia's ability to fund the war.However, most countries decided not to take sides, and only the closest US allies-Australia, Japan, New Zealand and South Korea-followed suit.As the tenth largest economy in the world, South Korea's support was highly relevant both materially and in increasing the legitimacy of the western-and thus of NATO's-approach to the war.The US and European SPCs also needed to realize that their ammunition-especially artillery shell-stockpiles were inadequate to support Ukraine in a long war.As the South Korean army's reserves were known to be substantial in this regard, NATO leaders-including the alliance's secretary-general, and US and Polish officials-turned to South Korea. 45Although the South Korean SPC was unwilling to send lethal aid to Ukraine directly, it sold and rented at least 600,000 artillery shells to the US.As a result, the latter had more flexibility for providing artillery shells to Ukraine from its stockpile, which had begun to run lower than the US SPC was comfortable with. 46nternational Affairs 100: 2, 2024

Structural factor 3: previous collaborations
The third structural factor is previous collaborations between South Korea and NATO.The idea is that experiences of collaboration are path dependent: that is, the 'structure that prevails after a specific moment in time (often a critical juncture) shapes the subsequent trajectory in ways that make alternative institutional designs substantially less likely to triumph'. 47According to Paul Pierson, there are increasing returns in following the extant processes because the cost of switching paths increases over time.More specifically, this is due to the large set-up or fixed costs associated with establishing the initial cooperative frameworks.But after that, the learning effects accrue over time among stakeholders, and then the coordination effects kick in when stakeholders adopt the same behaviour making collaboration smoother.As a result, finally, adaptive expectations emerge when stakeholders develop a perception that existing collaborations will work in the future, creating a self-fulfilling prophecy. 48spects of path dependency can be observed in South Korea's cooperation with NATO.For example, the US rationale for bringing South Korea closer to NATO was the two states' shared experiences of training and fighting side by side in previous conflicts.The US under-secretary for political affairs, Nicholas Burns, commented just prior to the NATO summit in Riga in 2006 that: One of the … major proposals that President Bush will take to the NATO summit is a proposal to establish a program of global partners … we seek a partnership with [Australia, Japan and South Korea] so that we can train more intensively from a military point of view and grow closer to them because we are deployed with them.Australia, South Korea and Japan are in Afghanistan.They have all been in Iraq … in the Balkans. 49us collaborations in Afghanistan paved the way for establishing formal relations between the SPCs of NATO and South Korea, and thereafter they expanded quickly.When South Korean foreign minister Ban Ki-moon visited NATO headquarters in December 2005 and addressed the North Atlantic Council-being the first South Korean government official to do so-details of South Korean cooperation with NATO were slim, with Ban noting that the two were 'acting together for peace and stability, as well as reconstruction in Iraq and Afghanistan'. 50This is especially notable when compared to the speech made by Ban's successor, Yoon Byung-se, during his visit to NATO headquarters in 2016, when he listed South Korea's cooperation with NATO across a far wider range of issues, citing the missions in Afghanistan and Libya, and cooperation in the fields of counterterrorism, anti-piracy and cyber defence. 51nternational Affairs 100: 2, 2024 In terms of South Korean activity in Afghanistan, South Korea's SPC deployed military and civilian personnel to ISAF between 2002 and 2007 as well as between 2010 and 2013. 52On the first occasion, South Korea deployed about 200 engineering and medical troops in 2002, but they were withdrawn after Taliban insurgents kidnapped 23 South Korean missionaries in 2007 from Ghazni province.Two hostages were killed, with the remaining 21 being released, after South Korea agreed that its military personnel would leave the country by the end of the year. 53espite opposing public opinion, South Korea decided to deploy approximately 200 military and 150 civilian and police personnel, within the framework of the South Korean provincial reconstruction team, to Afghanistan between 2010 and 2013, primarily engaging in reconstruction operations in Parwan province. 54urthermore, South Korea made a significant contribution-over US$319 million in the period to February 2021-to NATO's Afghan National Army (ANA) Trust Fund, aimed at improving the ANA's capacities. 55ooperation between South Korea and NATO within the ISAF mission created more institutional links, generating learning and coordination effects.In 2012, South Korea entered into an Individual Partnership Cooperation Programme (IPCP) with NATO.This was revised in 2017 and 2019, before the IPCP was upgraded to an Individually Tailored Partnership Programme in July 2023, which broadened the sectors of cooperation between the two sides. 56Furthermore, under the 2014 Partnership Interoperability Initiative, South Korea has been working to improve interoperability between NATO members and partners. 57The South Korean SPC also participates in lower-level practical NATO projects within the framework of the alliance's Science for Peace and Security Programme.Accordingly, South Korean scientists cooperate with NATO nations on CBRN defence, and on NATO-led research projects related to counterterrorism focused on the detection of explosives and firearms. 58At the same time-albeit as mainly symbolical gestures-successive NATO secretaries-general, 59 and even the North Atlantic Council, 60 have expressed their support to South Korea in terms of nuclear non-proliferation and security issues regarding the Korean peninsula.
International Affairs 100: 2, 2024 Collaboration between South Korea and European NATO members has also improved in the past decade, thanks to South Korea's expanding arms exports.Even before the start of the war in Ukraine, European states procured weapon systems from South Korea in significant quantities.For example, Estonia, Finland, Norway, Poland and Turkey bought K9 self-propelled howitzers.The UK's Royal Navy procured four tanker ships from South Korea for the British Royal Fleet Auxiliary,61 while Turkey's new main battle tank, the Altay, is based on the design of the South Korean K2 Black Panther. 62hus, South Korea's alliance with the US created the opportunity to launch a process where the SPCs of NATO and South Korea started working together more closely-initially in Afghanistan, but then in other areas.However, this relationship has since evolved beyond the US-South Korea alliance, due to the significant expansion of South Korea's institutional ties with NATO as an organization, as well as its security collaborations with individual European NATO members via arms exports.
Accordingly, previous collaborations, especially in Afghanistan, laid down the large set-up costs for NATO-South Korea cooperation, and further interactions between them generated learning effects.These dynamics helped the two sides work together more effectively, which manifested in the 2012 signature of the first IPCP.Thus, South Korea and NATO started to coordinate some of their actions to a greater extent, which generated adaptive expectations of successful cooperation between the SPCs of South Korea and NATO in the future.Path dependency explains these incremental improvements in the past, which provide necessary foundations for more recent initiatives.Without these previous collaborations that created shared experiences, mechanisms for cooperation and personal relationships, the new initiatives could not have been established quickly.

Situational factor 1: strong leadership and interpersonal 'chemistry'
Although structures are fundamental to provide the foundations for cooperation, situational factors trigger the launch of a collaboration, and explain why a certain collaboration started at a specific time.In the first of our two situational factors, key stakeholders from a minimum of two SPCs must work together closely and put in sufficient additional effort (including time and investment) to make a new initiative work.This also requires strong leadership from these stakeholders, who can be high-level politicians, military officers or civil servants in critical positions, and who act as the 'engines' of the collaboration.Usually, they like each otheror at least they do not dislike each other-which helps them set processes in motion.Often, this interpersonal chemistry is a necessary precondition to make a new initiative work because people do not like to spend time or be associated with others they do not like.63 International Affairs 100: 2, 2024 Based on the insights of social psychology, two elements are relevant when leaders like each other and develop interpersonal chemistry in the context of international cooperation: propinquity (the state of being physically close to another) and similarity. 64In the case of propinquity, leaders normally meet and have the chance to interact when engaged in bilateral or multinational negotiations.While a prerequisite for collaboration, this is not sufficient to build interpersonal chemistry.Thus, similarity in relevant areas provides a common platform.It makes communication more effective 'as similar individuals have to be less guarded among each other because they share similar values and attitudes'. 65The perception of similarity is often influenced by the group we belong to, and we are drawn to those individuals who are similar to the archetype of our relevant group. 66or instance, Nicolas Sarkozy, who served as president of France between 2007 and 2012, was seen as more Atlanticist in orientation than his predecessors, as his policies seemed to be aligned more closely with the archetype of NATO members, the US and the UK.Under Sarkozy's presidency, for example, France finally reintegrated into the military wing of NATO in 2009, after a 43-year absence, and also co-led the NATO intervention in 2011 in Libya together with David Cameron, the British prime minister at the time.Thanks to his perceived similarity to the archetype of key NATO members, he was called 'Sarko the American' and 'The New Margaret Thatcher', which helped him to develop interpersonal chemistry with NATO leaders. 67imilarly to Sarkozy, South Korea's President Yoon Suk Yeol, elected in March 2022, has taken a stance on several crucial international issues whichcompared to his predecessors-has seemed closer to the policies of the US and other relevant NATO members, creating the perception that he was more similar to the 'archetypical' NATO leaders.Yoon's predecessor, the liberal president Moon Jae-in (2017-2022) had often seemed to be out of step with US policies, which generated friction between the South Korean and US governments.Moon adopted a more 'dovish' approach in negotiations on the denuclearization of North Korea, compared, for example, to the hawkish approach of the Donald J. Trump administration in the US.Moon was also seen to nourish closer ties with China, both for economic reasons and in the hope that China could play a constructive role in convincing North Korea to give up its nuclear weapons.During the first phase of the Russian invasion of Ukraine in early 2022, the Moon administration was reportedly described by a former US Department of State official as having undermined the perception of international solidarity among democratic and allied nations, for initially being reluctant to condemn Russian actions and implement sanctions. 68nternational Affairs 100: 2, 2024 Whereas Moon changed his approach towards the end of his term in office, to align more closely with the West, from the start of his presidency Yoon Suk Yeol used similar language and pursued a similar foreign policy approach to NATO members (especially the United States).Yoon laid much more emphasis on the relevance of universal democratic values in his 'global pivotal state' agenda, changing the perception that South Korea tilted towards China, and adopted a more hawkish approach to North Korea than his predecessor. 69He also sided more clearly with the West and against Russia on the issue of Ukraine. 70During NATO's 2022 Madrid summit, he stated that 'as a new structure of competitions and conflicts is taking shape, there is also a movement that denies the universal values that we have been protecting', referring to the Russian invasion of Ukraine and China's responsibility in the international community. 71This resonated well with NATO's SPC, and Secretary-General Stoltenberg subsequently highlighted during a visit to Seoul in January 2023 that South Korea 'can count on NATO'. 72oon's stance on key foreign and security policy issues has thus been broadly similar to the position adopted by the SPCs of archetypical NATO members.
Further evidence of a positive rapport between President Yoon and NATO members could be observed in the numerous bilateral talks held with European politicians on the sidelines of the Madrid and Vilnius NATO summits, held in 2022 and 2023 respectively.However, the leadership of and the interpersonal chemistry between Yoon and US President Joe Biden have been instrumental in the rapid development of the South Korea-NATO relationship.At the same time, for Yoon and Biden, improving the relationship between South Korea and the alliance has not been a primary foreign policy goal, rather a tool to achieve their broader aims.Both leaders have emphasized the necessity for democratic countries with shared values to work together more closely.For instance, in 2021 the Biden administration launched the 'Summit for Democracy' initiative, a global virtual summit for leaders from government, civil society and the private sector 'to set forth an affirmative agenda for democratic renewal and to tackle the greatest threats faced by democracies today through collective action'. 73The Biden administration has also worked to deepen collaboration between allies and partners in several formats, 74 while Yoon has improved South Korea's relations with Japan both bilaterally and through the trilateral partnership between South Korea, the US and Japan.Furthermore, the Yoon administration started to play a more International Affairs 100: 2, 2024 constructive role with its engagement with NATO, the G7 and the UN.Yoon and Biden have also been perceived by some observers to be in lockstep on other major foreign policy issues-such as North Korea's denuclearization and China's aggressive behaviour-and economic affairs.As Derek Grossman, a defence analyst at RAND Corporation, suggests, 'Yoon's overlapping tenure with Biden heralds a golden era in the U.S.-South Korea alliance'. 75These similarities between the two leaders in terms of values and aims has provided the context for the improvement of NATO-South Korea relations.
At the same time, similarities based on political attitudes are not necessarily enough to establish good chemistry between two leaders.If they find that they are similar in other areas that are personally relevant for them, that also helps.Although Biden and Yoon differ in many ways, their personalities are similar in relevant aspects; for instance, their pets and families are very important to both, which they bonded over during their first official meeting in May 2022. 76They established excellent interpersonal chemistry since then, which was epitomized in a state dinner in the White House in April 2023, when at the end of the event, President Biden invited President Yoon to sing a song; Yoon took the microphone and sang 'American Pie' for the audience.Previously, Joe Biden emphasized the relevance of good personal relations in foreign affairs.Thus, the good relationship between Biden and Yoon is even more important for establishing a healthy US-South Korea alliance, which also indirectly helped to improve NATO-South Korea cooperation. 77tuational factor 2: a supportive political milieu A supportive political milieu towards security cooperation positively shapes the development of closer relations between actors.This is because SPCs do not work in a vacuum, but are influenced by the environment that surrounds them as much as by their own inner dynamics.Indeed, a supportive political milieu is often necessary to launch a new collaboration and galvanize support both within and outside the relevant SPCs.In addition, it helps to 'convince and change the attitudes of those who are sceptical or … hostile' to the initiative. 78he Russian invasion of Ukraine in February 2022 drastically changed Europe's security landscape; it also generated a supportive political milieu in the SPCs of both NATO and South Korea.It was the first time since the Second World War that a state had launched a full-scale war against another country on the European continent.Members of both NATO and the European Union immediately condemned Russia's actions, implemented a series of punitive sanctions, increased International Affairs 100: 2, 2024 the readiness and troop numbers on NATO's eastern flank and provided significant military aid to Ukraine.Furthermore, western countries sought support from other parts of the world to isolate Russia politically and economically.Many European NATO members also wanted to speed up their own military modernization.They feared either that Russian expansionism might not end with Ukraine, and that Russia could go on to attack new NATO members-especially some of the previously communist countries-or that the war in Ukraine could escalate to a broader conflict.This situation generated a supportive political milieu in Europe to deepen collaboration with South Korea.As previously discussed, South Korea's support as a major economy in the imposition of sanctions against Russia and the provision of aid to Ukraine was deemed important, which also increased the legitimacy of western actions.South Korea's role as a major weapons supplier to European NATO members has also been cemented in the context of the war in Ukraine.This new layer of collaboration with NATO members developed rapidly from 2022 as South Korea proved that it could deliver complex weapon systems in large quantities to NATO countries quickly, while European and US arms producers struggled to meet the new demand.In 2022, Poland ordered weapon systems from South Korea in deals potentially worth US$15 billion.According to the agreements, South Korea was to deliver 48 FA-50 fighter jets, 672 K9 self-propelled howitzers, 288 Chunmoo multiple missile launchers and 980 K2 Black Panther main battle tanks, of which 180 were to be supplied from South Korea by 2025, and the remaining 800 produced in Poland by 2030.A separate, previous agreement with Norway also materialized in the procurement by that country of a further number of South Korean K9 howitzers and K10 ammunition resupply vehicles. 79Half a dozen other central and northern European countries are reportedly considering buying weapon systems from South Korea. 80he SPCs of NATO and South Korea currently share a threat perception, at least in part.NATO's 2022 Strategic Concept elaborates on the security challenges NATO faces and corresponding tasks.It not only stresses that 'the Russian Federation is the most significant and direct threat to Allies' security', 81 and that 'the People's Republic of China's … stated ambitions and coercive policies challenge our interests, security and values', 82 but also sees the strengthening partnership between the two as being counter to NATO's values and interests.The document emphasizes the importance of the Indo-Pacific as a strategically relevant region, in that 'developments in that region can directly affect Euro-Atlantic security'. 83outh Korea's concern regarding Russia and China is compounded by the longstanding tensions on the Korean peninsula.North Korea has shown strong International Affairs 100: 2, 2024 support for Russia after its invasion of Ukraine, recognizing Ukraine's Donetsk and Luhansk provinces as independent republics. 84North Korea has likely sent millions of artillery shells and large numbers of missiles to support Russia's war efforts in Ukraine, while Russia probably provides fighter jets, nuclear-related technologies and air-defence systems to North Korea. 85Russia has also shielded North Korea on the international stage by blocking further international sanctions against the North Korean regime. 86Thus, for South Korea, Russia's belligerence is not simply a threat to European security but also has more local repercussions.Meanwhile, in September 2022 President Yoon commented that if China were to start a military conflict with Taiwan, 'there will be increased possibility [sic] of North Korean provocation'. 87Thus, South Korea's cooperation with NATO on issues concerning Russia and China is linked to its core interest in maintaining peace and stability on the Korean peninsula.
To be sure, some of the groundwork that led to the visible deepening of South Korea-NATO relations had been made prior to Russia's invasion of Ukraine.For example, bids to join NATO's CCDCOE cyber defence hub began in 2019.Furthermore, during the initial Russian invasion of Ukraine, South Korea was undergoing a period of presidential transition; outgoing president Moon Jae-in's initial reluctance to fully support the international community in condemning the invasion changed during the last months of his term, paving the way for the continuation of support from the incoming Yoon.Both the South Korean and NATO SPCs viewed their deepening relations positively, but events in Ukraine generated a supportive political milieu that sped up their collaboration significantly.

Conclusions
Returning to the question posed at the outset of this article, why have South Korea-NATO relations deepened rapidly, and why has it happened at this particular moment, this article highlights that the five factors identified by Nemeth's theory on defence cooperation have been instrumental in deepening South Korea-NATO relations.These relations have not developed in a linear manner, but rather have come into effect through mutually reinforcing interactions spanning the five factors.Thus, the case of the quickly evolving South Korea-NATO relations illustrates how the understanding of these five factors could provide opportunities for SPCs to jump-start collaboration.For policy-makers, an acute understanding of the various moving parts of security cooperation could help them to seize International Affairs 100: 2, 2024 opportunities at certain junctures or, conversely, to decide instead to bide their time when relations between two states hit a rocky stage.Viewed through such a lens, the theory brings into question the utility of looking at security cooperation through a purely realist perspective of structural conditions in the international system or state interests.Nemeth's approach highlights that understanding the needs of relevant SPCs, as well as their past relationships and, more generally, the importance of the 'softer' side of cooperation-including factors such as interpersonal relations and the general political milieu-could make or shake, if not break, state relations.
Nemeth's theory is criticized on the basis that it moves away from a statecentric approach by focusing on policy communities and considers personal relations among officials, when they are 'notoriously difficult to operationalise and measure'. 88This is a correct observation, and more conceptual work is definitely needed in this regard.However, it does not mean that scholars and analysts should not try to grasp these significant dynamics of security cooperation.Or, that they should ignore the insights of practitioners who experience the relevance of good interpersonal relationships among key officials and the significance of understanding the history, needs, values and organizational setting of the partner policy communities.
Thus, the South Korea-NATO case not only points out that a certain level of perception of 'we-ness', previous collaborations among SPCs and the perceived lack of resources that the partner SPCs can help with play crucial roles in establishing new collaborations.It also shows that while these factors may have yielded prospective areas of cooperation, such potential could only be realized because the personal relations and the political context were also aligned.The strong leadership shown by Presidents Biden and Yoon with respect to working closely together-and with other democratic countries with which they share values-has provided the background for their rapid furthering of South Korea-NATO relations.Furthermore, their personal interactions demonstrate a positive chemistry that also has a beneficial effect on the South Korea-NATO relationship.In contrast, this trend of rapidly deepening, ever more meaningful South Korea-NATO relations would have been difficult to imagine under the previous US and South Korean presidents, Trump and Moon, because of their strained personal relationship and Trump's open skepticism towards NATO.Finally, the Russian invasion of Ukraine also created a supportive political milieu towards deepening South Korea-NATO cooperation, by generating a sense of urgency and the recognition that the Indo-Pacific and the Euro-Atlantic regions are interconnected.
Thanks to these dynamics, the foundations of South Korea-NATO relations strengthened and will likely become even more robust, as both parties are interested in consolidating their relations and as the constellation of the five factors described earlier supports these dynamics.Although there is still plenty of room International Affairs 100: 2, 2024 for further collaboration, there is a clear limit as to how far the cooperation between NATO and South Korea can progress.For instance, South Korea will not become a member of NATO, as there is no appetite from either party for this.Thus, in the case of a military conflict between South and North Korea, NATO would support South Korea politically, but it is unlikely that NATO as an organization would be involved in the conflict directly.At the same time, certain NATO members might, individually, provide tangible support in such an eventuality as their collaboration grows with South Korea-thanks to the fact that the security community formed by South Korea and NATO is becoming stronger.
Finally, Nemeth's theory also posits that when the constellation of the studied five factors becomes less conducive to security cooperation, the progress of security collaborations slows down.Although structural factors change slowly, situational factors are quick to change.Leaders change, and the supportive political milieu might rapidly disappear.Thus, the main job for NATO and South Korean officials-or for any officials who are involved in deepening any security cooperation when the constellation of the factors is right-is to institutionalize their collaborations further and establish a web of good interpersonal relationships between officials, military officers and experts at different levels.This way, they can make their relations more resilient, ensuring that partnerships will endure through times when certain factors will be less favourable towards cooperation.