In 2017, a new trend emerged among allies to describe the relation of Sweden and Finland to NATO. In May, when the US Secretary of Defense James Mattis met with his Swedish counterpart Peter Hultqvist in Washington DC, he declared that if the Russians were to come, ‘America will not abandon democratic allies and partners, and we will stand with Sweden (…). It’s not a NATO ally, but it is still, from our point of view, a friend and an ally.’Footnote 1 Similarly, in May, at the yearly security conference Globsec in Bratislava, the Lithuanian Foreign Minister Linas Linkevicius referred to Sweden and Finland as very active in the diplomacy of NATO and as ‘allies, not neutral, in the development of the Baltic Sea region’. Speaking at a panel in Riga in June, NATO official Eric Povel described Sweden and Finland as ‘not members but perhaps half-members’. The same month, the UK Defense Secretary Michael Fallon took it one step further. In an exclusive interview with Sweden´s largest newspaper Dagens Nyheter, he stated the Joint Expeditionary Force (JEF), led by the Brits, would support Sweden in case it was threatened by a crisis in the region.Footnote 2 And in an interview with Finnish media, Fallon claimed that ‘as member of the JEF, Finland and Sweden can consider the other seven countries their natural allies.’Footnote 3

These congruent statements bring a key question to the fore: What makes an ally? Undisputedly, Sweden and Finland are close partners to NATO. After the Cold War, NATO opened up to forge a broad network of partnerships which gradually came to include around 40 nations worldwide. Sweden and Finland were quick to join the Partnership for Peace (PfP) in 1994, the Euro-Atlantic Partnership Council (EAPC) in 1997 and the Enhanced Opportunities Partners (EOP) in 2014. During these 20 years, Sweden and Finland moved from being neutral, hardly interoperable states to active EU members with almost full NATO interoperability. The EOP, which allows for tailor-made, deepened cooperation with NATO, was offered at the Wales Summit to a handful of partners which were considered to be the closest to the alliance: Australia, Georgia, Jordan, Sweden and Finland. Through this step, Sweden and Finland left the other military non-aligned European states such as Austria, Ireland and Switzerland behind and positioned themselves even closer to NATO.

The development of NATO’s partnerships has been covered in research, but the distinction between an ally and a partner has generally been taken for granted and not problematized.Footnote 4 In this perspective, an ally is a nation who has signed the North Atlantic Treaty, and a partner has not. Clearly in this regard, Sweden and Finland are not formal allies. Nonetheless, a gray zone exists between partner and ally, at the point where informal (i.e., non-treaty-based) alliances meet formal alliances (treaty-based). History is full of alliances lacking legal status, which opens up for the possibility of a more open approach to the notion of an ally also with regard to NATO.

The aim of this article is to shed light on the phenomena expressed above, i.e., the gray zone when close partners become so close that they, in fact, are viewed as allies, rather than partners. The ambition is to provide new insights into how and why such a shift comes about, using Sweden and Finland as a case study. The article also aims at contributing to research on what constitutes an ally, by introducing the concept of ‘informal ally’, in contrast to ‘formal ally, and examines it through a synthesized analytical framework that builds on elements from realist, liberal and constructivist theories. The synthesized analytical framework is used to evaluate the process of ever closer partner cooperation. By extensive interviews, the article also makes an empirical contribution to the research literature on how the contemporary security policy elite views NATO.

By introducing the concept of an ‘informal ally’, it is possible to examine whether Sweden and Finland can be viewed as such. Therefore, the author advances that an informal ally is defined as ‘a country that has not formally signed an alliance treaty, but who is perceived by the members of a formal alliance as a trustworthy country that in case of a major crisis or war would, without hesitation, align on their side to meet the threat in concert’.

For Sweden, an ‘informal ally’ discourse can be traced to the origins of NATO. In the British thinking prior to the establishment of the alliance, the military took on quite a realistic stance with regard to Scandinavia. Despite the area’s strategic importance to the UK, the Scandinavians were only desired in the treaty if they included Sweden, which was supposedly well armed.Footnote 5 The UK saw Sweden, Norway and Denmark as ‘one formidable military combination’, where Sweden could provide arms to the others. Sweden, on the other hand, had put forward the idea of a Nordic defense union, partly out of consideration for Finland’s special situation with regard to the Soviet Union. In 1948, Finland and the Soviet Union signed an agreement on ‘friendship, cooperation and mutual assistance’ which in practice made it impossible for Finland to officially join the West. To secure the North, Sweden wanted the Nordics to form a neutral block in between the East and the West.Footnote 6 The British, who feared overstretch, supported a Nordic defense union which would not demand a commitment from Britain, but the Americans did not approve. The American planners were against Scandinavian neutrality, since it would not secure the essential strategic objectives in the North. They did not believe that neutrality could be maintained and that the Scandinavian countries would be able to resist Soviet pressure for bases and facilities. In addition, it would not allow the allies to get access to the necessary base facilities or the right to overfly Scandinavian territory, which was extremely important for the strategic bombing campaign because Scandinavia was directly on the route the bombers would take from the USA to important Soviet targets. Hence, there was a major risk that in case of war, both allies and the Soviets would find it difficult to respect Scandinavian neutrality, especially in the air. Neutrality would also hamper prior planning which could lead to disaster, as had been the case with Holland and Belgium in 1940. The Americans preferred a neutral Sweden, that could support Finland and thereby serve to stabilize the North, and Norwegian and Danish membership in the Atlantic pact rather than a Scandinavian defense pact with no treaty links to western powers.Footnote 7 In the end, this is how it turned out.

Hence, Sweden’s neutrality was from the origins of NATO part of considerations made by the West on how to win a war against the Soviets. Sweden´s neutrality served a purpose for the West, and if it failed, the West would come to assist Sweden. Secretly and informally, a range of preparations for wartime cooperation with NATO allies, with Norway, Denmark, the UK and the USA at the core, were made during the 1950s and 1960s.Footnote 8 This included ‘the extension of the runways of certain Swedish airbases to accommodate allied bombers, technical and procedural measures to facilitate overflights, the designation of military liason teams for dispatch to allied capitals and headquarters, and the installation of secure means of communications between allied and Swedish military headquarters.’ Combined plans were worked out with Denmark and Norway for the coordination of air surveillance and the use of signals and ciphers. There was also cooperation in the field of intelligence.Footnote 9 Norway and AFNORTH were the main routes to NATO. By 1953, it was decided that AFNORTH should be the terminus for planning contacts with Sweden, and the same year, AFNORTH had worked out a new defense plan in which Sweden was taken into account much more than before. Sweden also kept close contact with USAFE, with headquarters in Wiesbaden, and the major NATO air commands on the continent.Footnote 10

Obviously, the situation of Finland was quite different during the cold war. Strategically, the West counted on that in case of a war with the Soviet Union, Finland would fall into the sphere of the Soviets. When the Soviet Union dissolved, Finland got rid of the restrictions posed on it by the friendship pact and joined the European Union in 1995. For Finland, joining the EU had apparent security implications as it firmly positioned Finland into the West. Hence, the fact that the EU is a political alliance with a potential of becoming a defense alliance, as expressed in article 42.7 of the Lisbon Treaty, serves the Finnish interests well.

In the modern era and in relation to being an informal ally, it is important to recognize that the EU membership brings a treaty-based commitment of Sweden and Finland to the European NATO allies that they will indeed act in solidarity in case any member is attacked. In addition, both Sweden and Finland have deep bilateral defense cooperation with the USA, as well as with each other. The Finnish–Swedish defense cooperation officially includes joint wartime planning.

For NATO, the concept of informal allies is central to address. Its strategic concept builds on a clear distinction between ‘collective defense’, which is for allies exclusively, and ‘cooperative security’, which includes partners. How does the existence of informal allies impact NATO in decision-making, operational planning and response to a crisis in Sweden and Finland? How can NATO balance between solving its core tasks as efficient as possible without undermining itself as a multilateral institution? On one hand, informal allies can in practice serve to strengthen collective defense due to the preparations made for joint action in case it would be necessary, but on the other, if not openly recognized, it can serve to blur, and thus undermine, the joint commitment made by allies.

For Sweden and Finland, the deepened collaboration put labels such as ‘military non-alignment’ (Sweden) and ‘a country which does not belong to any military alliance’ (Finland) into test.Footnote 11 Both countries officially abandoned the concept of neutrality when joining the EU in 1995. Still, neither country has officially applied for NATO membership. Being a close partner to NATO was uncontroversial when the cooperation took place far away, but as it moves closer to territorial defense, the stakes get higher to remain outside of the alliance. What does it take for countries such as Sweden and Finland to maintain their degree of informal alliance, once they have achieved it?

The choice to use both Sweden and Finland in the case study springs from their closeness, when it comes to factors such as relationship with NATO, geographic position, bilateral defense cooperation and security interdependence. It is also broadly presumed that if Sweden and Finland were to join NATO, they would do it hand in hand, as was the case with the EU in 1995. From NATO’s perspective, Sweden and Finland are viewed more or less as twins.

The empirical material builds to quite a large extent on interviews with key persons in NATO, both in the international staff and the diplomatic representations, as well as in national governments. In addition, qualitative content analysis has been applied on official NATO documents as well as on statements and comments by relevant foreign policy figures.

Analytical framework

The distinction between a formal and informal ally is not a broadly addressed theme in the alliance literature, regardless of whether a realist, liberal or constructivist approach is applied, but some guidance can be found in each. In the following analysis, elements from all three approaches will be applied in a synthesized attempt to explore what makes an ally.

The realist approach focuses on threats, security and common interests among sovereign nation states in forming and maintaining alliances. As Thucydides put it in The Peloponnesian War: ‘In an alliance, the only safe guarantee is an equality of mutual fear’.Footnote 12 With the emphasis put on military force in the realist perspective, military alliances become an important element in the search for and exercise of power. A state must seek assistance if it is unable to guarantee its own security through its own armed forces or to achieve sufficient power relative to other members of the international system. If two or more states face a common threat, the need for military assistance can result in a military alliance. From a realistic perspective, this alliance can be formal, and treaty based, or more informal and ad hoc in nature. The distinction between formality and informality is subordinate to the fundamental impetus, which lies both in the convergence of the interests of the parties (security and/or power) and in the existence of a common threat.Footnote 13 Accordingly, the threat perception among states seeking to form alliances is central, here defined as ‘perception of a threat to national sovereignty by another state’.

A liberal approach balances the formal–informal aspects of an alliance in favor of more emphasis on legal foundations such as international treaties, institutions and interdependencies. The fact that there is a North Atlantic Treaty for allies to sign, and a well-established institutional function for NATO, matters from this perspective.Footnote 14 With regard to alliances, liberalism would emphasize the importance of being part of institutions in the formation of state interests, and in changing conceptions of self-interest.Footnote 15 International institutions exist ‘largely because they facilitate self-interested cooperation by reducing uncertainty, thus stabilizing expectations’. The institutions provide functions of information-provision, monitoring and reduction of transaction costs.Footnote 16 There are also those liberalists who emphasize how democracy at the national level reinforces institutional ties internationally.Footnote 17 Consequently, being outside of an international institution, such as NATO, would require states, who seek influence over the formation of states self-interests, to compensate with a higher level of political energy, for instance through increased bilateral contacts, or by creating informal settings that allow for formation processes. It is also possible to attain a certain degree of institutionalization, without being fully inside, as is the case with NATO and its partnerships.Footnote 18 Using the liberal approach, it becomes apparent that institutional commitment is required, defined here as ‘the willingness of a state to join institutional frameworks, and to comply by and contribute to institutional rules and order’.

The constructivist approach concentrates on identity, sentiment and culture as fundamental defining measurements for an alliance. Though not a constructivist himself, Karl Deutsch and his notion of security communities has been picked up by this school of thought. It is not the institution of NATO which is critical, but rather its collective space, in NATO’s case the transatlantic community. Nor does the external threat matter, but the internal commitment to keep peace among members. The foundation for a security community is a ‘sense of community’ including ‘mutual sympathy and loyalties, of “we-feeling”, trust and mutual consideration; of partial identification in terms of self-images and interests; of mutually successful predictions of behavior and of cooperative action in accordance with it.’Footnote 19 Collective identity is at the core of constructivist analysis. Identity always deals with the issue of ourselves in relations to others: it tells you who you are, it tells others who you are and it tells you who the others are.Footnote 20 A key aspect for constructivists is that identity is not ‘fixed by nature, given by God or planned by intentional behavior, but rather that it is constituted in relation to difference.’Footnote 21 How we perceive and define ourselves determine what group we belong to. Following this approach, community becomes a core notion, here defined as ‘states bound together by mutual trust, loyalty, we-feeling and a shared vision that distinguish this group from a defined ‘other’.

By synthesizing the approaches above, three critical questions can be applied to the case study of Sweden and Finland in order to explore what makes an ally:

  1. (1)

    Do Sweden and Finland share security interests and threat perceptions with NATO?

  2. (2)

    Do Sweden and Finland share a commitment to NATO as a transatlantic institution?

  3. (3)

    Do Sweden and Finland identify themselves as being part of a Western community of mutual trust, in which peace is kept among members and in which Russia is seen as “the other”?

The primary reason for NATO’s existence since its formation has been collective defense against external attack; to have allies in defense of a common enemy and to restore the balance of power in Europe, which was perceived as disrupted by Soviet aggressiveness.Footnote 22 When the Berlin Wall fell, NATO shifted focus to international missions and opened up for cooperation with partners. NATO marked the importance it put on partnerships by making it one of its main tasks as ‘cooperative security’ in the Strategic Concept of 2010, while ‘collective defense’ remained a main task for allies only. The partnerships are regulated through various official programs, which provide institutional settings and establish ties for the relations.

When the Partnership for Peace (PfP) was launched in 1994, Sweden and Finland were quick to join. Their interest was not to become NATO members, but to contribute to a common European security architecture, and to improve the conduct of international peace operations.Footnote 23 Starting from a very low level, Sweden and Finland developed interoperability through the Planning and Review Process (PARP), by participation in military and civilian exercises, and by contributing troops to all NATO-led international missions. The extensive bodies of the PfP and the Euro-Atlantic Partnership Council (EAPC) with NATO plus 22 European, Caucasian and Central Asian partners, have played a central role for Sweden and Finland in building collaboration with the alliance. However, despite the principle of self-differentiation, the formats have their limits when it comes to deepening cooperation, given the broad variety of members and their national agendas. Soon after the Russia annexation of Crimea in 2014, Sweden and Finland were invited at the Wales summit to join the Enhanced Opportunities Program (EOP), which allowed for tailor-made, deepened cooperation with NATO. The development of the EOP can be divided into three phases. In the following, these phases will be described and analyzed from the years 2013–2017 using the three questions defined above as guidance.

Enhanced partnership in the making

Phase I: Formation process up until the Wales summit in September 2014

The idea to form a special partner program for a group of highly qualified partners started to take shape in 2013. The initiative came from Sweden, with solid support from Finland, and was mainly driven by a worry of deteriorated levels of interoperability with NATO in light of the termination of the troop mission in Afghanistan as announced by the Obama administration upon his re-election as president in 2012.

At the time, Sweden and Finland had well-established positions as security providers to stability in and around Europe. Having contributed to all NATO-led international missions from the Balkans to Libya, while being well situated in one of the most peaceful regions of the world, the Baltic Sea area, Sweden and Finland were appreciated as valuable partners, sometimes informally referred to as ‘non-NATO allies’.Footnote 24

In 2013, it was widely acknowledged that the appetite for large-scale international missions, like in the Balkans or Afghanistan, was low among leading nations. This in turn put focus on the possibility for partners to participate in advanced exercises, and to link into NATO command structures in peacetime, in order to keep core operative capabilities and to be able to maintain interoperability. The Swedish Defense Commission recognized the need to be pro-active in this regard in its security report in spring 2013.Footnote 25

At this point, Sweden and Finland started drifting apart from the other European non-allied countries, such as Austria, Ireland and Switzerland, a group that traditionally had cooperated closely as partners and contributing nations to NATO-led missions. The agendas started to diverge, as Sweden and Finland wanted to continue to develop close relations with NATO and had few political restrictions on how to proceed. This in turn enabled Sweden and Finland to move ahead with concrete steps and suggestions to the alliance.Footnote 26

Threat perceptions

The EOP was born in a context of security, not defense. NATO had after the Cold War been confronted with the option of either ‘go out of area or go out of business’ and had settled for the former, transforming itself and its force structure to expeditionary missions outside of NATO territory, while European members took the opportunity to further reduce defense spending in what appeared as peaceful times on the continent. At this time, the international legal system still seemed to function rather well, alongside tendencies of globalization and interdependencies that put focus way from states as actors toward other phenomena, such as climate change and terrorist groups. Threat and security definitions were broadly defined both in scope and time. Power politics had to a large extent shifted from hard power to soft power.Footnote 27

In 2013, Sweden designated a general to work alongside allies, in order to develop a concept that would fit the needs of Sweden and Finland within the framework of the Connected Forces Initiative.Footnote 28 That had never happened before and was a strong signal how far partners had integrated into NATO defense structures since the cold war had ended. There was an openness from NATO, and from the USA, in particular, to explore new forms of cooperation to ensure that partners continued to be ‘capable, up and running’ in case a crisis would occur. In this regard, close partners were an asset to the alliance. However, the crisis was still expected to occur outside of NATO territory. Although NATO, Sweden and Finland at the time when the EOP started to take shape would agree that a non-state actor such as al-Qaida was a threat to international peace, territorial concerns were in practice absent in the discussions. The military focus was mainly on security governance rather than collective defense. Preparations were focused on providing expeditionary, smaller units to international missions—though the Finns had kept more for territorial defense than the Swedes.

Upon the repeated alert from the Baltic states and Poland, caused by the Russian cyberattack on Estonia in 2007 and war on Georgia in 2008, the alliance had agreed to make generic contingency plans for them. Poland hosted a NATO exercise focusing on collective defense, Steadfast Jazz in the fall of 2013, but the strategic outlook and broad concern regarding developments eastward, was absent in NATO before the war in Ukraine.

The lack of a territorial, state-focused threat perception was also evident in founding document for the EOP endorsed by NATO Foreign Ministers in June 2014. The EOP offered a range of instruments to ‘encourage, facilitate and sustain’ partner contributions, including regular political consultations, assured participation in advanced exercises and early-stage planning, possibility to staff positions at NATO HQ and in the command structure and the possibility to share intelligence.Footnote 29 Most importantly, the EOP opened up for tailor-made, in-depth cooperation with NATO in whatever format that would be most suitable and efficient.

References were made ‘to enhance our joint ability to tackle security challenges, including through NATO-led operations and crisis management’ but these security challenges were not defined and the assumption is clearly that the tailor-made cooperation is about contributions to out-of-area operations.Footnote 30

Institutional commitment

Hence, at this point, the closeness to NATO by Sweden and Finland was not primarily shaped by common power interests or threat perceptions, but rather it was earned by participation with troops in all NATO-led, UN-mandated international peace support missions from the Balkans and onward. Militarily, this led to a high level of interoperability, and to a well-established respect for the professionalism of the Swedish and Finnish armed forces. Finland and Sweden had both joined the NATO Response Force (NRF) and its Response Forces Pool (RFP), Finland in 2008 and Sweden in 2013. The Finnish motivation was that it would benefit national defenses and increase interoperability with NATO troops.Footnote 31 Sweden emphasized the importance it had for the Swedish defense reform and the ability to participate in future multilateral exercises.Footnote 32

Politically, Sweden and Finland earned respect and trust among allies for standing by the US in the war on terrorism and by the international community in protecting the guiding principles of the UN charter and international law. There was a genuine interest within the alliance to have input from Sweden and Finland on policy issues, for instance on gender and resolution 1325. This in turn led to the possibility in 2011 to participate in decision-shaping processes in NATO, a question that Sweden and Finland had pushed hard to materialize together with Australia and New Zeeland. Thereby, Sweden and Finland got a fair amount of political influence in the missions that they participated in, which was positive for domestic political and public support for cooperation with NATO.Footnote 33

However, the interest for the transatlantic institution from Sweden and Finland was strictly limited to partnership. Membership was not a topic for discussion in neither country. Public support was low and stable around 25%, and for most political parties, it was a non-issue, with party programs in favor of remaining non-aligned. Finland differed from Sweden in that a possible membership was explicitly analyzed in a couple of white books and the NATO option was part of the official rhetoric to mark Finland’s independence in security policy choices, but in practice these nuances made no difference.Footnote 34

The commitment by Finland and Sweden to NATO, was stable but limited, and the relation kept at arm’s length. Both felt comfortable being outside of the military alliance, using membership in the EU, OSCE and the UN to supplement the close relation with NATO. Relations with Russia did not differ from the rest of Europe, that is, despite increasing question marks regarding its internal and external posture, expectations still were that Russia would comply with the European security order and that Georgia had been an unfortunate exception.

A Western community versus Russia

Since 1989, the NATO community had broadened extensively with 12 new members and more than 40 partnerships all over the world. In this ‘new NATO’, the distinction between being a partner or being an ally received little everyday attention. The east/west dichotomy was gone, and its vocabulary only appeared in reference to the cold war. The sense of we-feeling, of trust, of no risk of war among states, was strong. Who was ‘the other’? It was not an easy question to answer, and not a particularly relevant one either, as the world was perceived.

Russia, at this time, was not viewed as an enemy or a threat to the alliance. Quite on the contrary, Russia was, at least on paper, a strategic partner to NATO. It had by far the largest partner mission at NATO headquarters in Brussels, which implied that Russian diplomats and military officers moved freely in the corridors.

Since the end of the Cold War, NATO-Russian relations had pendulated with heights and lows, but despite sensitivities, the overall paradigm was cooperation and strive toward integration and inclusiveness, rather than competition and conflict.Footnote 35 In 1991, Russian president Boris Yeltsin wrote to NATO saying that Russia hoped to join the alliance sometime in the future.Footnote 36 NATO and Russia signed the Founding Act and formed the NATO-Russia Permanent Joint Council (PJC) in 1997. However, the NATO bombings of Yugoslavia in 1999, that were conducted without a UN mandate, quickly deteriorated the relationship. After the 9/11 attacks, cooperation gradually increased again, as NATO and Russia started collaborating on fighting terrorism. The Kremlin allowed US forces to use Russian air space for operations in Afghanistan, and tolerated the creation of US bases in former Central Asian republics of the Soviet Union. In 2002, the PJC was replaced by the NATO-Russia Partnership Council (NRC), which embraced the principle of parity with the ambition that allies and Russia would work as equal partners ‘in areas of common interest’. Still, deep divisions, including missile defense, NATO enlargement and its out-of-area role, prevailed.Footnote 37 During the Putin presidency, Russia started to drift from a pro-European orientation to a newly developed ideology of Eurasianism, which blamed current political and economic problems on western ideas and institutions, and embraced the idea of a Russian sphere of interest.Footnote 38 In August 2008, Russia invaded Georgia and NATO-Russia relations were paralyzed, though not for long, as numerous strategic and economic issues that required cooperation were given priority.Footnote 39 When the Obama administration took office in 2009, it presented a ‘reset’ policy with Russia, which was embraced by the alliance and led to a revitalization of the NRC, the signing of the New START Treaty between the USA and Russia, and an expansion of supply lines to Afghanistan through Russia. In the new NATO strategic concept of 2010, cooperation with Russia was mentioned as a matter of strategic importance. NATO countries offered to cooperate with Russia on anti-missile defense in Europe, an offer which Russia accepted and indulged in, but in 2011 the negotiations had led to a stalemate and no compromise was found.Footnote 40 Overall, after a few years, the reset was viewed by both Russia and the USA as a success, albeit modest in scope. It did not turn Russia into an ally, nor produced ideational alignment between Russia and the west.Footnote 41 Rather, the preferred option of Moscow remained the dissolution of the alliance and the creation of a different, new pan-European organization that would incorporate Russia as a full member, as described by president Medvedev in 2009.Footnote 42 NATO members, on the other hand, remained hesitant to entrust Moscow with decision-making prerogatives in areas of mutual interests. In spite of these hurdles, cooperation continued and NATO and Russia were cooperating as late as in the fall of 2013 on logistical flows to the Afghanistan mission and explored the possibility of collaboration on dismantling the al-Assad regime in Syria of chemical weapons.

In sum, during Phase I, the perception of a threat from another state was absent and hence not the subject of discussions or planning. While Sweden and Finland had no intentions of joining NATO, the institutional commitment to contribute as security providers to the alliance and take active part in its partnership frameworks and international missions, was high. The sense of community was strong, but its borders porous, and Russia was partly inside the community.

Phase II: Setting the stage on Baltic Sea security in 2014–2015

From 2014 onward, the renewed Russian threat spread beyond institutional boundaries and drew Sweden and Finland closer to NATO. However, this was not obvious from the start. When Russia annexed of Crimea in early March 2014, NATO had to act along two dimensions: what to do to support Ukraine, and what to do to assure the security of members by the Eastern border. Military, NATO clearly prioritized the latter, as the ‘red line’ between membership and non-membership in the alliance became brutally clear for Ukraine. Defense measures did not apply to partners, not even close ones. Instead, in the balance between resolve and not increasing tensions, the alliance settled for some rather modest deterrence measures and show of force on its territory. The Americans took the lead by sending 600 troops to the Baltic states and Poland for continuous exercises, in addition to enforcing the Air Policing Mission in Baltic airspace in collaboration with a range of allies.

For Sweden and Finland, it was a rather brutal awakening when Poland evoked article 4 in early March, and the usually open doors at NATO Headquarters closed for partners.Footnote 43 Sweden and Finland could participate at NAC meetings when they addressed Afghanistan, but when Baltic Sea security was on the table, they were not invited and the diplomats and military officers had to work the corridors in the headquarters in order to get information.Footnote 44

Prior to the Wales summit, while the EOP was still taking shape, the security environment of Sweden and Finland rapidly deteriorated as a consequence of the Russian behavior in Ukraine and increased military activities in the vicinity of both countries. Consequently, national defense became a clear priority. In addition, Sweden and Finland initiated deepened bilateral defense collaboration, including joint planning for crisis or war.Footnote 45

Between March 2014 and the summit in September 2014, NATO was pre-occupied by immediate response and reassurance measures. The strategic aspects of the Baltic Sea area did not get attention until after the summit, when the EOP had been established. Thus, the task of filling the EOP with content for deepened collaboration, using the format of 28 + 2, that is, all allies together with Sweden and Finland, coincided with NATO turning its strategic gaze toward the region.Footnote 46

Threat perception

Russia’s behavior was a core concern. NATO’s shift began after the repeated Russian incursions into Nordic and Baltic air space and an intensive submarine hunt in Stockholm’s archipelago in October 2014. Reuters’ top news story on 28 October 2014, which was widely spread, was ‘Nordic, Baltic states Face “New Normal” of Russian Military Threat’. Within NATO, these events caused internal discussions, since both members and partners were affected by Russian activities.Footnote 47 The term ‘new normal’ came to be a guideline to describe increased Russian military activity and assertive behavior in the region.Footnote 48 It helped shape a common perception and understanding of the Russian threat and that it was not temporary, which was a fundamental factor in moving the alliance forward.Footnote 49

The more NATO looked at the Baltic Sea region, the clearer it became that it must be viewed as one military strategic area. With the short distances involved, in combination with the long range of today’s weapons systems, and modern society’s vulnerability, not least in terms of IT systems and energy flows, mutual dependency was great, regardless of whether the countries around the Baltic Sea were members of the Alliance or not. To these considerations, the speed by which modern crises and wars occur must be added, as well as the complications provided by hybrid warfare in assessing threats and identifying aggressors. As a consequence, it was an obvious interest for both the Alliance and Sweden and Finland to collaborate on these issues.Footnote 50

Institutional commitment

A crucial factor in developing the enhanced partnership was the use of NATO committees to push the process forward. The first meeting in the new 28 + 2 format between NATO, Sweden and Finland, took place in the deputy ambassador circle in January 2015. During this meeting, the Danes initiated a military assessment of the security situation in the Baltic Sea region. Another landmark happened on 22 April, when Secretary General Jens Stoltenberg chaired a NAC meeting with Sweden and Finland. For the first time in many years, the council discussed the security situation in the Baltic Sea region. The basis for the discussion was the military assessment with its focus on ‘a new normal’, in which Russia’s intensified activities could no longer be considered as a passing storm. It was perceived that Russia was testing NATO’s determination to stand up for security in the region, with regard to both members and third parties, and hybrid warfare was a central part.

The conclusion about ‘a new normal’ received wide agreement around the table. In general, Russia had a strong interest in securing access to the Baltic Sea. A number of areas were identified where cooperation with Sweden and Finland should be intensified in the future, including the exchange of situational awareness in the region, the exchange of information about hybrid warfare, connection with NATO’s rapid reaction forces (NRF), and coordination of training and exercises in the region.Footnote 51

Baltic Sea security also reached the agenda at the meeting of foreign ministers at Antalya in Turkey in May 2015. At the following meeting of foreign ministers in Brussels in December, work had proceeded within relevant working groups, with contributions from Sweden and Finland. A report was presented which contained continued tasks both in the military and political organization of NATO, including a biannual update of the military assessment for the foreseeable future and a political-military assessment of the situation in the Baltic Sea region to be produced for the next ministerial meeting in May 2016.Footnote 52

Another driving force for enhancing partnerships with Sweden and Finland was that the need to cooperate closely on Baltic sea matters was urgent. Sweden and Finland had contributions in terms of for instance intelligence and situational awareness, military capabilities and territory for exercises, offers that were of great interest to the alliance.Footnote 53 However, the prospect that Sweden and Finland would join the alliance any time soon appeared distant for domestic political reasons. Attitudes toward NATO membership started shifting in Sweden in 2014, while Finland remained stable. The Conservatives, along with the Center Party and Christian Democrats, joined the Liberals in pushing for Swedish membership. However, the push did not come until the fall of 2014, just after the parties had lost their governmental power. The Social Democratic—Green government that took office instead, did not share that vision.Footnote 54 As for public opinion, polls have since 2014 indicated that a plurality (ranging between 35 and 49% depending on the poll) would like to see Sweden joining NATO. However, public opinion tends to also consist of a large group of ‘uncertain’ voters, and to follow party lines, where voters for the Social Democrats, the Green party and the Left Party are still mostly against membership.Footnote 55

Both Finland and Sweden signed a Host Nation Support Agreement (HNS) with NATO at the Wales summit in 2014, and by May 2016 it had been approved by the national parliaments. While in Finland, the HNS caused little official debate, the debate was heated in Sweden, since the signing of the HNS was used by NATO sceptics to argue against membership. The HNS thus fed into the larger political debate on joining NATO, and at one point there were question marks whether it would pass parliament. In the end, it was smoothly approved.Footnote 56

A Western community versus Russia

After some initial stumbling, the illegal annexation of Crimea in 2014 led to a clear break of trust between Russia and the alliance. The Russian military aggression in Ukraine took NATO by surprise. Despite having followed the developments closely, the use of Russian military force was unexpected. At the meeting in the NAC on March 2, some members were questioning whether those little green men actually were Russians.Footnote 57 The reaction from NATO members indicate that up to this point, the cooperation that NATO and Russia had maintained in selected areas of mutual interests, also contributed to uphold a sense of community with Russia, and that the use of military force and the violations of international law in Georgia in 2008 would not be repeated. AFP reported that an anonymous diplomat from one of the larger members said; ‘No one seriously believes there will be a military response’.Footnote 58 Poland felt the need to underline the seriousness of the situation by calling for article 4 consultations, sensing that other European allies were not as concerned about what happened as they ought to be. Sweden and Finland followed NATO and the EU closely in their reactions toward Russia’s behavior. Almost all practical cooperation with Russia was suspended, and Sweden and Finland joined the EU sanctions against Russia.Footnote 59

To sum up Phase II, there was during this period a growing concern regarding Russia, with a threat perception pending between ‘passing storm’ and ‘climate change’, until it settled on a level where a ‘new normal’ had been established at a higher threat level. In Sweden, opinion shifted in favor of NATO membership, while in Finland it remained opposed. Nevertheless, institutional commitment as partners deepened even further through a Baltic Sea focus in the EOP and the signing of HNS Treaties. Trust between the West and Russia was abruptly broken by the illegal annexation of Crimea and cooperation was halted. Sweden and Finland were clearly positioned within the community of the West, while Russia now was fully on the outside.

Phase III: From cooperative security to collective defense in 2016–2017

From mid-2014 onward, a range of tabletop exercises, so-called war games, were conducted to get a grip of the military strategic playing field in the Baltic Sea region. Major findings included the difficulty to reinforce the Baltic states and Poland, and the role Sweden and Finland could play for the alliance in defending the Baltics. The exercises served to deepen the discussions on Baltic Sea security in the 28 + 2 format to encompass not merely how to perceive the threat but also how to deter and defend against it. The partnership moved from out-of-area crisis management closer to territorial defense, and thereby, collective defense.

Threat perception

Its regional military superiority, combined with its proximity to allies, was the major concern regarding Russia. The war games that the American think-tank RAND, in close cooperation with the Pentagon, conducted in 2014 and 2015 were influential for shaping contingency planning. The exercises examined the shape and probable outcome of a near-term Russian invasion of the Baltic states, and concluded that NATO could not successfully defend the territory of its most exposed members. To prevent the rapid overrun of the Baltic states a force of about seven brigades were needed, according to RAND.Footnote 60 The failure to defend the Baltics was mainly due to lack of forces in Europe, lack of readiness and mobility, and an adversary with ‘the world’s best surface-to-air missiles’ and ‘not afraid to use heavy artillery’, as the former deputy assistant secretary of defense for force development, David Ochmanek, put it.Footnote 61

As the military analysis of the region deepened, the dilemma posed by the Suwalki gap, and the anti-access/area-denial (A2AD) created by Russia in the Kaliningrad enclave, became increasingly apparent. The Suwalki gap, a term coined by the Estonian president Toomas Hendrik Ilves, is a 100-km-wide corridor between Kaliningrad and Belarus that allied reinforcements would need to use to get to the Baltic states in an emergency. Should Russia cut it off, other NATO members would not have land access to the Baltic States from the rest of the Alliance’s territory. In that case, NATO could only help the region from the sea and air, which also would be difficult given the efficient defensive bubble stemming from Kaliningrad.Footnote 62 Hence, at a closer look, the initial idea to rely on rapid reinforcements such as the new spearhead force (VJTF) was not doable. For NATO, this led to the establishment in 2017 of the Enhanced Forward Presence (EFP), i.e., multinational combat ready battle groups, altogether 4600 troops, in the Baltics and Poland. Lead nations were the UK (Estonia), Canada (Latvia), Germany (Lithuania) and the USA (Poland). Additional eleven allies contributed to the battlegroups. In Poland, the USA also placed an armored brigade combat team of 3500 troops as part of its operation Atlantic Resolve and moved its division headquarters and command from Baumholder in Germany to Poznan in Poland.Footnote 63

The roles of Sweden and Finland were explicitly dealt with in two tabletop exercises in early 2016. The Center for a New American Security (CNAS) conducted an exercise in Washington DC in February 2016, which identified a number of areas for improvement in terms of NATO’s strategy and cohesiveness in the face of surprise aggression. One key insight was the value of relationships with Sweden and Finland, not least in requests for use of territory in case of crisis and the need for information-sharing. With regard to Sweden, the ‘enormous strategic importance’ of the island of Gotland in the Baltic Sea was highlighted, and the risk of a Russian land grab at an early stage in order to expand its anti-access/area-denial over the Baltics.Footnote 64 As later concluded by the Swedish inquiry on NATO membership, ‘Russia may have an interest in deploying its air defense systems to Swedish territory so as to strengthen its capacity to deny NATO access to airspace over the Baltic Sea. Operations against Sweden may precede the main attack against the Baltic States.’Footnote 65 At a visit to Sweden in April 2016, Deputy Defense Secretary Robert Work stated that ‘the U.S. would take it very, very seriously if there were a threat against Gotland’.Footnote 66 Due to its central importance for the security of the region, Sweden re-militarized Gotland in 2016. Lieutenant General Ben Hodges, the commanding general of the US Army forces in Europe, described Gotland as a key location on his visit to the island in July 2017, addressing the Swedish soldiers: ‘You have a strategically very important task here. I do not think there is any island anywhere that is more important.’Footnote 67 Ben Hodges visited Gotland to prepare for American participation in the national defense exercise Aurora, which was the largest military exercise conducted by Sweden in September 2017 in over 20 years. Almost 20,000 Swedish troops participated, joined by military units from Denmark, Estonia, Finland, France, Lithuania, Norway, and the USA, which sent 1400 troops, including a Patriot missile battery, helicopters, and a National Guard tank company—in sum, a clear statement on the strategic importance of Sweden in the defense of the Baltics.

Shortly after Assured Resolve, in March 2016, NATO conducted its yearly tabletop exercise (CMX) to which Sweden and Finland were invited, focusing on an escalating crisis in the Baltic Sea region. This exercise, repeated in 2017 but with a different geographic scope, gave key findings on the need for more developed procedures for early communication, information-sharing and political consultations between NATO and its closest partners.Footnote 68 Lessons learned from the CMX exercises illustrated the importance to NATO of having Sweden and Finland involved as much as possible in order to conduct any serious defense of the Baltics. Hence, the red line regarding membership tended to be defined more and more by Sweden and Finland, than by the alliance.Footnote 69 Meanwhile, the distance to the other close partner nations increased. As for the other European partner nations, Austria, Switzerland and Ireland, the drift that started in 2013, due to differences in the willingness to come closer to NATO, accelerated. The difference in threat perception with regard to Russia was the key factor. For Sweden and Finland, the security situation deteriorated fast and was a serious concern, while Austria, Switzerland and Ireland were still more focused on international crisis management.Footnote 70

Institutional commitment

In practical terms, this was the period when Sweden and Finland entered the gray zone between being a partner and being an ally, as they integrated into the working-level of the alliance institutional framework. At the Warsaw summit in July 2016, political consultations were one of the key areas highlighted for further cooperation between NATO and Sweden and Finland, alongside joint exercises and shared situational awareness.Footnote 71 It became evident that Sweden and Finland had reached a degree of partnership with NATO that the other EOP countries did not have. For the first time in history, the Swedish Prime Minister Stefan Löfven and the Finnish President Sauli Niinistö had dinner with the Heads of States of NATO. No other partner country participated. The core of their discussion was security of the Baltic Sea region. The special relation that had developed was also highlighted in the final communiqué of the summit, with a specific mentioning of only the two Nordic countries.Footnote 72 A month later, American Vice President Joe Biden visited Sweden and publically stated that “no one should misunderstand, neither Mr. Putin or anyone else, that this is inviolable territory. Period. Period. Period.”Footnote 73

The distinction of Sweden and Finland among partners, as visible at the Warsaw summit, became even more elaborate and explicit during 2017, as the routine of inviting Sweden and Finland to a broad range of working committee meetings in NATO was settled. Swedish and Finnish ministers were also exclusively invited to the NATO defense and foreign ministerial meetings, to join discussions on Baltic Sea security or EU-NATO cooperation. The special status of Sweden and Finland had been ‘pretty much established’. There was a common sense and an understanding in the alliance that they were different partners ‘because they have means to project stability, and are keepers of high moral ground’.Footnote 74 It helped that Swedish and Finnish officials fit smoothly into the work culture of the alliance. They were defined as being part of the ‘Western camp’ and recognized as EU members. They knew how to avoid minefields and how to communicate. Clearly, they were perceived as contributing to the institutional framework and as trustworthy, also in more practical terms such as intelligence sharing.Footnote 75 Even though the closeness was established, it was an ongoing effort for Sweden and Finland to maintain the crucial feeling of win–win. Hence, a range of national skills were offered to share with the alliance, such as in-depth knowledge of Russia, Baltic Sea situational awareness, special forces competence, gender and resolution 1325 competence, intelligence, cyber security, comprehensive security, countering of hybrid threats, as well the positions as EU members to push for increased NATO-EU cooperation, which was a priority for Secretary General Jens Stoltenberg.Footnote 76

The inquiries on NATO membership made in both Sweden and Finland during 2016 did not change public opinion nor political party positions. The importance of NATO for transatlantic security was underlined, the support for a close partnership with NATO remained strong, but Stockholm and Helsinki did not during 2016–2017 match the practical rapprochement to NATO with a push to formally join the institution. Hence in 2017, two major challenges prevailed for Sweden and Finland in relation to NATO in order to improve readiness in case of a crisis or war: political consultations and operational planning.

With regard to political consultations, the dilemma for Sweden and Finland was twofold. They did not automatically get invited to consultations initiated by allies in reference to article 4 or 5 of the North Atlantic Treaty, and they lacked mechanisms to initiate themselves consultations ‘whenever (…) the territorial integrity, political independence or security of any of the Parties is threatened’, as stipulated in article 4. Indeed, the PfP framework document from 1994 stated that ‘NATO will consult with any active participant in the Partnership if that Partner perceives a direct threat to its territorial integrity, political independence, or security’ (article 8), but that was not equivalent to sitting side by side with allies trying to get a grip of a crisis situation that was likely to affect the Baltic Sea region, which was more what Sweden and Finland looked for. The political-military framework for out-of-area missions also contains mechanisms for political consultation. The framework was established in 2011 after a push from partners such as Sweden, Finland, Australia and New Zealand. At that time, it had made sense to the alliance, that if a nation contributed with troops on the ground and risked the lives of soldiers, that nation should be part of information-sharing and decision-shaping.Footnote 77 The framework has been applied during crisis management exercises with Sweden and Finland in order to test its relevance. A lesson learned was that the framework was not fully applicable to collective defense situations. For international missions, troop contribution gave the status as security provider, while troop contribution was not likely to be the first offer in a crisis situation that might activate collective defense, but rather intelligence, or access to territory such as airspace or sea upon requests from allies. In order to underline their commitment to be active security providers in a crisis situation, Sweden and Finland stressed their status as EU members and the solidarity to act in accordance with article 42.7 of the EU Treaty of Lisbon.Footnote 78

Thus, Sweden and Finland aimed at preparing as much as possible in peacetime in order to be able to cooperate quickly and closely in case of a crisis situation that could lead to collective defense measures, such as when NATO evokes article 4 or 5 of the North Atlantic Treaty. A political decision in Stockholm, Helsinki and at NATO would be needed in order to activate the crisis cooperation, but the advantage would be to have prepared as far as possible in advance the decision-making procedures and information-sharing requirements that would be needed in such a situation.Footnote 79 At this time, NATO officials pointed out that Sweden and Finland would most likely be part from the beginning of any consultations that addressed Baltic Sea security anyway. The dilemma and likely exclusion would rather arise if the consultations concerned ‘cross-cutting issues’, such as Russia in a broader sense, developments in the Middle East, or counter-terrorism, where it would be less apparent for NATO that Sweden and Finland were relevant actors to include around the table.Footnote 80

Joint operational planning was politically more sensitive than political consultation mechanisms, since it could hardly be decided on a case-by-case setting, but would have to take place continuously and include some sort of assumption regarding military action beyond peacetime. During 2017, information exchange at various levels regarding operational planning took place, aiming at understanding each other’s processes and intentions given that NATO, Sweden and Finland share the same operational environment.Footnote 81 This was, however, a rather limited procedure. In order to be efficient, Swedish and Finnish operational planning should at least be integrated with the Graduate Response Planning that exists for the Baltic states and Poland.Footnote 82 Sweden and Finland have an agreement that officially encompass joint planning beyond peacetime, though security guarantees are not included from either side, but there is no such equivalent agreement between NATO, and Sweden or Finland.Footnote 83 The disadvantages that the lack of a treaty-based order for operative cooperation with NATO poses on the Swedish defense in terms of credibility and preparedness was highlighted both in the inquiry on NATO membership presented in September 2016, and in an official document from the Armed Forces to the Ministry of Defense in March 2017.Footnote 84

A Western community versus Russia

With regard to Russia, both Sweden and Finland were in congruence with the positions of NATO and the EU. At the Warsaw summit, NATO formulated its new posture on Russia in terms of ‘deterrence/defence and dialogue’.Footnote 85 The political stance of Sweden and Finland followed the alliance closely in this regard. Sweden and Finland agreed with the alliance that deterrence supported stability, and that the aim was to avoid any situation in the Baltic Sea region in which territory would need to be recovered. During 2016, official inquiries in both Sweden and Finland evaluated NATO membership. The inquiries reached similar conclusions on deterrence. The most tangible military consequence of Swedish NATO membership would be to dispel the current uncertainty regarding common action in the event of a Baltic Sea crisis, and that the West’s deterrence therefore most probably would increase. Finnish membership of NATO would evidently strengthen Finland’s immediate security as it would be included in the Article 5 guarantees and strengthen the deterrence of any potential attack against the country.Footnote 86

However, just before the NATO Warsaw summit in July 2016, Finland managed to stir up some dust regarding its trustworthiness. Finland has a unique position in Europe in its relationship with Russia, stemming back from being part of the Russian empire for more than 100 years, and then from successfully handling an aggressive neighbor as a young independent nation from 1917 onward. Thus, throughout the deteriorated security situation in the past years, Finland has kept political contacts at the highest level. Some controversy within NATO arose, when the Finnish president at a meeting with the Russian president suggested cooperation in the Baltic sea area on transponders by aircraft as a confidence-building measure with NATO, a suggestion that had not been sufficiently anchored with allies in advance. Political consultations beforehand were expected by a close partner to NATO.Footnote 87 Externally, however, the alliance kept a polite tone and welcomed the initiative, also a sign of the closeness Finland had achieved with NATO.

In Moscow, the close relation of Sweden and Finland to NATO was carefully watched. The military non-aligned Nordic countries were consistently referred to as ‘neutrals’. Russian representatives repeatedly warn that a Swedish or Finnish NATO membership would have military consequences for Russia. President Putin himself claimed that if ‘Sweden joins NATO this will affect our relations in a negative way because we will consider that the infrastructure of the military bloc now approaches us from the Swedish side. We will interpret that as an additional threat for Russia and we will think about how to eliminate this threat.’Footnote 88 He also suggested that Russia could move its troops closer to the Finnish–Russian border if Finland joins NATO.Footnote 89

To sum up, during Phase III, consensus on a threat perception had emerged, as well as a realization that Sweden and Finland were crucial for the alliance to meet that threat successfully, since the Baltic Sea area was one military strategic area. With regard to institutional commitment, Sweden and Finland positioned themselves as ‘closest partners’ to NATO, with an increased distance to other partners, to the extent that they were referred to as ‘allies’, despite limitations on political consultation mechanisms and operational planning. However, membership was still not on the political agenda in neither Stockholm nor Helsinki. Sweden and Finland stayed firm with the alliance on policy toward Russia.


For the process of partnership development, the synthesized analytical framework used suggests that changes and convergence in threat perception is the core factor that has positioned NATO, Sweden and Finland closer to each other than ever before—without Sweden and Finland crossing the line and formally becoming members of the alliance. However, institutional commitment and identity matter as well. The political energy invested by Sweden and Finland in order to confirm institutional commitment, has been necessary in order to make efficient use of the EOP and to achieve a high degree of institutionalization, without being fully inside. Furthermore, that Sweden and Finland have taken clear positions versus Russia has spurred a sense of loyalty and trust. Hence, in NATO, both are perceived as part of the ‘Western camp’ alongside formal members of the alliance.

Do Sweden and Finland share security interests and threat perceptions with NATO? The short answer is yes. By breaching international law and using military force in Georgia and Ukraine, Russia has become a potential threat to national sovereignty. For Sweden, Finland and NATO, the situation is serious; the threat is real and not likely to pass soon.

The language which emerged in 2017, in which Sweden and Finland were described by some NATO leaders as ‘allies’, reflected that NATO had reached the conclusion that it was in its interest to have Sweden and Finland as informal allies in case of a crisis or war in the region, in order to increase chances to successfully defend the Baltics. Tabletop exercises with Sweden and Finland had demonstrated the mutual interests of the parties to cooperate on defense, and on their mutual dependency to successfully handle the common threat. The realist approach helps explain what pushed Sweden and Finland into their unprecedented status in relation to the alliance, and also why other partners, even those with a similar position in terms of institutional commitment and community belonging, were not. The key factor was the emergence of a threat to national sovereignty and the will, capacity and necessity to deal with that threat in concert. Treaty or not treaty became less relevant in this regard. The main difference to partners such as Austria, Switzerland, Ireland but also Australia and New Zealand, was the level of threat perception of Russia to their state sovereignty. The main difference to partners such as Ukraine, Georgia and Moldova, was that the alliance did not need them to defend the Baltics. There was no shared interest or need. From 2014 onward, NATO pragmatically moved partner collaboration with Sweden and Finland from the realm of ‘cooperative security’ to ‘collective defense’. The shift is remarkable given both the history of NATO and the historically cautious non-aligned Nordic countries.

Do Sweden and Finland share a commitment to NATO as a transatlantic institution? Partly. On one hand, for many years, Sweden and Finland have valued their relationship with NATO. Alongside the EU, OSCE and the UN, NATO is viewed as part of a web of indispensable security institutions and the transatlantic link is recognized as crucial for European security. The question of NATO membership has been debated in both countries during 2014–2017, with a clear shift in Sweden to a more favorable public opinion as well as greater parliamentary support. On the other, membership has not seriously been put on the table neither in Stockholm nor in Helsinki. Sweden and Finland remain hesitant toward a full formal commitment to NATO.

In the past years, the position as closest partners to NATO would not have been possible without the tailor-made cooperation provided by the EOP, which opened up a regular presence in a range of NATO working committees and ministerial meetings. In addition, the signings of the HNS agreements were crucial for advancing planning and exercises. However, these institutional elements per se do not lead to closeness. In order to have influence and get information as a non-member, a substantial amount of political energy is needed. There is no automatic information flow or seat at the table. This has forced Sweden and Finland to be more inventive, active and pushy regarding cooperative initiatives than otherwise would have been needed. The liberal approach highlights the importance of the political energy which Sweden and Finland have exercised, in comparison with other non-aligned European states and EOP nations, who nowadays are left out of forums in which Sweden and Finland are welcome. Clearly, the explicit political will to be security providers in the new European environment has made a difference for Swedes and Finns in relation to NATO and put them in a category of their own. The challenge ahead is to stay relevant enough to keep the privileged position, given that the factor that caused the shift, the emerging threat perception, stays in place.

Do Sweden and Finland identify themselves as part of a Western community of trust in which Russia is seen as ‘the other’? The answer is yes. Sweden and Finland clearly identify themselves as part of a Western community in which Russia is not included, due to its aggressive behavior toward its neighbors, its lack of compliance with international law and its attempts to undermine democracy and cohesion in the West. The trust that was built up in the period following the cold war was broken in 2014. During the cold war, Sweden and Finland were neutrals, officially balancing between the Western and the Eastern bloc. That period definitely came to an end in 1995, when Sweden and Finland both joined the EU. As EU members, both are bound to act in solidarity if another member state is threatened. Despite geographical closeness to Russia, and for Finland, close historical ties, the deteriorated security situation in Europe has not led to a shift on how Sweden or Finland define themselves, nor Russia, in the new setting. In NATO, both are perceived as part of the ‘Western camp’ and within the circle of loyalty and trust that has its origins in the years of joint out-of-area crisis management. The main contribution of the constructivist approach is that it pinpoints these underlying factors. The existence of trust and ‘we-feeling’ clearly facilitated, fastened and smoothened processes needed for the ‘informal ally’ status to start functioning for Sweden and Finland. In contrast, for partners such as Ukraine, Georgia and Moldova, being fully inside the community is difficult as long as ‘the other’ is occupying parts of their territories.

What makes an ally?

This article has made conceptual as well as empirical contributions by introducing the concept of “informal ally”, and examining a process of partner development that has not been illuminated in detail before. The analysis in the article suggests that four core elements need to be in place in order for a close partner to transition into an informal ally. First and most importantly, there needs to be a common threat to national sovereignty, and a realization that defense against that threat is needed in concert, regardless of the formal status of all nations involved. In short, NATO needs Sweden and Finland for the defense of the Baltics. Secondly, there must be a certain degree of institutionalization, despite lack of formal membership. The key factor of the EOP was to let Sweden and Finland participate in the working procedures of the alliance on an equal footing with the members. Thirdly, the partner needs to have a high degree of political will and energy to pursue a closer relationship. A central element is to underline mutual interests and create a sense of win–win for both partners and allies. Both Sweden and Finland have been successful in this regard. Fourthly, there needs to be identification with the community which constitutes the institution: a sense of trust and belonging. Sweden and Finland define themselves, and are perceived as, part of the West with its norms, values and practices.

Accordingly, there is reasonable support to argue that Sweden and Finland in the past years have gained status as informal allies, that is they are perceived by the members of NATO as trustworthy, and would, in case of a major crisis or war would, without hesitation, align on side of the alliance to meet the threat in concert, despite not having signed the North Atlantic treaty. The approximate time for this transition was the second half of 2016. As was the ambition with integrating Sweden and Finland into the Connected Forces Initiative, they are nowadays ‘capable, up and running’ in case a crisis would occur.

The distinction between a formal and an informal ally is important, as is awareness of strengths and weaknesses with the status both for the countries and for NATO. Being an informal ally has its advantages. Most likely, Sweden and Finland would, in a threatening situation in the Baltic Sea region, get, and would be expected to give, support to the alliance. The status allows for some preparations to be made in this regard. However, the limitation of the informal ally status for Sweden and Finland is equally important to highlight: it has a restricted geographic scope, since it is only applicable in the Baltic Sea region, it lacks formal access to the decision-making of the alliance, it does not include joint operational planning, and it contains a transparency deficit since the status is not officially recognized. Furthermore, it is a fragile position which depends on the circumstances. A continued perception in NATO of Russia as a potential vital threat is a prerequisite. If the level of tensions would decrease, Sweden and Finland risk diminishing their relevance to NATO as the focus would shift elsewhere. Further research should look deeper into bilateral dependencies of this status, firsthand the USA, as well as the significance of EU membership, since the EU has its own security guarantee clause. A comparative study between Sweden, Finland, and other partners in NATO’s vicinity such as Georgia or Ukraine could be useful in this regard.

The main advantage for NATO in having Sweden and Finland in this position is that both deterrence and defense of the Baltics improve. It facilitates quite substantially for the alliance to fulfil its obligations under article 5 of the North Atlantic Treaty, should a crisis or war situation emerge. In addition, Sweden and Finland could be useful as EU members, bridging between the institutions, given the likely need for NATO and the EU to cooperate closely in case of a severe crisis in the Baltics. A third dimension is the advantage of having two countries with strong commitments to the norms and values of the institution integrated in the internal work procedures. On the other hand, it risks devaluing the meaning of security guarantees, since these are not treaty bound for an informal ally. It could also undermine the institutional strength of NATO by blurring the decision-making process. Furthermore, since NATO cannot take the availability of Swedish or Finnish capabilities formally for granted, the defense planners always have to plan and ensure that they have access to sufficient capabilities to be able to act without Sweden or Finland, even if that is unrealistic. Hence, it brings an additional element of ambiguity to operational planning.

‘There are no rules, we invent as we go along’. That is how a NATO diplomat explained the culture and evolvement of the alliance to a Swedish diplomat in year 2000. The rapprochement by NATO of partners to the realm of collective defense seems to be yet another phenomenon of pragmatic evolution in the alliance. As NATO turns 70, it needs to strike the right balance between solving its core tasks as efficiently as possible on one hand, and not undermining itself as a multilateral institution on the other. Illuminating the concept of informal allies, and discussing its possibilities and limitations, could be one useful step ahead.