Two Years in NATO, Finland is Searching for a Plan B

The air in Helsinki is heavy with irony. Finnish attitudes towards NATO changed abruptly following Russia’s full-scale invasion of Ukraine. Just two months after the start of the invasion, almost 80% of the public had come around to support NATO membership. When Finland entered the Alliance on 4th April 2023, parts of the political establishment hailed this as the end point of the country’s long trek to join the West, finally making Finland a full member of a security community of like-minded liberal democracies.

Then came the re-election of Donald Trump. President Trump’s harsh treatment of Ukraine as well as a conditional commitment to NATO’s collective defence evaporated any lingering sense of complacency in Helsinki. Just 50% of the public now say they trust the United States. Prime Minister Petteri Orpo told citizens that whilst he retained confidence in Finland’s most important ally, he also acknowledged that the United States had changed. Just two years ago, Finland’s NATO accession had seemingly cracked its century-old dilemma of surviving next door to its former overlord and great power neighbour, Russia. Now, according to an unconfirmed newspaper report, Finland has begun exploring a Plan B in case NATO's Article 5 fails to function as intended.

This comment evaluates Helsinki’s options regarding its national security. We argue that a viable Plan B exists – the ‘Nordic Plus’ – but, like all European defence initiatives, it comes with uncertainties and cannot compensate for potential US disengagement.

Plan A: American-Led Alliance

Finland’s Plan A builds heavily on its alliance relationship with the United States, which played a central role in supporting Finland’s path to NATO. President Biden affirmed America’s ‘ironclad commitment’ to Article 5, directed his military to conduct nearly constant training missions in Finland, and visited Helsinki to mark the country’s ‘NATOzation’. Furthermore, in December 2023, Finland signed a Defence Cooperation agreement with the United States, anticipating American investments in Finnish military infrastructure as well as a regular presence of US troops and personnel in the country.

However, two months into his second term, President Trump has already made clear his interest-based and transactional approach to foreign affairs, as well as his tendency to shift his perception of US interests from one day to the next. For the next four years, the implementation of Article 5 relies on a somewhat whimsical American president who has on multiple public occasions expressed confidence in Russian president Vladimir Putin over America’s longstanding European allies.

Indeed, President Trump has noted that there is an ocean between America and Europe. Consequently, Russia’s territorial ambitions in Eastern Europe do not appear to pose a threat to the United States. To paraphrase Lord Ismay, NATO was established to keep America in, Germany down, and Russia out – a goal that previous US administrations largely upheld. By contrast, influential figures within the Trump administration have expressed indifference towards Europe’s security, support for Alternative für Deutschland, and sympathy for certain aspects of Russia’s foreign policy. As a result, at the time of writing, the credibility of Finland’s Plan A is undeniably eroding.

Nordic Plus as a Plan B

What would a possible Plan B look like? It can be summed up as ‘Nordic Plus’. NATO membership has unlocked significant new potential for military cooperation between Finland and its allies. In this context, Finnish leaders will likely turn to Sweden, Norway, the United Kingdom, and, potentially, France. Logistically, the Scandinavian countries play a crucial role in supplying Finland in the event of war, and Finland has been advocating for major improvements in Nordic connectivity and infrastructure. Moreover, these countries can potentially provide considerable military capabilities. For instance, together the countries have an air force of 200 modern fighter jets. However, as affluent nations, Norway and Sweden could still allocate significant additional societal resources to collective defence, such as considerably expanding the conscription system for force generation.

When it comes to larger European powers, the United Kingdom, seen as a serious security provider with a genuine interest in Northern European security, could potentially offer a wide spectrum of military support on land, at sea and in the air, also providing special capabilities such as intelligence, reconnaissance and surveillance. Moreover, France – an additional European heavyweight – could also contribute to Finland’s deterrence, particularly through its nuclear weapons. It is not inconceivable that Finnish skies could soon host training missions by nuclear-capable French fighter jets if Paris is truly prepared to introduce a European dimension to its nuclear deterrence.

Furthermore, Finland’s traditional support of the EU’s defence efforts will remain significant. Finland has given its full support to the European Commission’s recent efforts to foster European rearmament and strongly urged EU leaders to convene a defence-focused summit, which eventually took place on 6 March. Fiscally conservative Helsinki is also warming up to the idea of raising common debt to bankroll the building of an autonomous European military-industrial complex. It is also prepared to make the defence-related articles of the Lisbon Treaty more credible and concrete.

Despite the lingering mistrust towards the United States, Finnish decision makers will strive to keep the transatlantic flame alive. Finland will do everything it can to present itself as a helpful partner to President Trump and thus avoid direct rupture in the transatlantic linkage. There is also the hope that America may recommit to playing the role of a backstop in NATO under a future administration.

Is Europe Able to Muster Military Force?

Unsurprisingly, the key question for Finnish foreign policy today is whether Plan B will work if it needs to be duly activated. The key challenge for Finnish foreign policy is ensuring Western European commitment to the defence of NATO’s frontline states. However, Western European countries that are not directly threatened by Russia will be tempted to free ride by outsourcing defence costs to their Eastern European neighbours. Perceptions of the threat are inversely affected by a country’s distance from Russia. Even Finland’s closest neighbours, Sweden and Norway, enjoy the benefit of having a Finnish buffer between them and Russia, although they also have a considerable interest in Finland’s territorial integrity.

Despite the ongoing momentum for Europe to step up, the continent, lacking corporate agency in defence matters, will face significant challenges in coordinating its security in the absence of American leadership, if history is any guide. In the 1920s, America decided to disengage from Europe’s problems. Britain and France stepped into the breach and sought to ensure European security. Unfortunately, Britain and France were economically and militarily too weak to effectively deter the ambitions of revisionist states.

These material limitations were amplified by arguments that questioned the relevance of Eastern European conflicts for Western European security. For instance, Foreign Secretary Austen Chamberlain wrote in 1925 that no British government would risk the bones of a British soldier over an Eastern European border dispute. Similar voices in the 2020s will undoubtedly be amplified by Russia. Russia will continue to assert that it has no territorial ambitions beyond Ukraine and seeks mutually beneficial relations with Western European countries, including Germany.

If Plan B Fails

Finally, there is the follow up question of what Finland might do if Europe’s efforts to mobilise collective deterrence against Russia are unsuccessful. Currently, there is very little public discussion of a Plan C. Finnish decision makers are focused on reassuring a jittery public by underlining Finland’s efforts to foster European security coordination, day-to-day cooperation with the United States, and independent defence capability. These efforts undoubtedly ensure sufficient deterrence whilst Russia’s offensive capability remains engaged in Ukraine.

However, a scenario in which Europe's efforts to mobilise collective deterrence against Russia fail is not inconceivable. This would significantly weaken Finland's deterrence, as Ukraine's experience demonstrates that Finland can only successfully deter Russia with external support. If maintaining allied support for Finnish security becomes increasingly difficult, it is possible that Finland will explore the possibility of a Plan C based on rapprochement with Russia. That said, Helsinki will take this road with considerable reluctance and only if forced by external circumstances and would still retain significant national defence capabilities.

Finland’s two-year rollercoaster ride in NATO underlines the futility of predicting the future in international relations. The next two years in Finnish foreign policy will undoubtedly contain new surprises. Even so, it is likely that Helsinki will aim to keep its options open and has possibly already begun laying conditions for all eventualities. Though Finland is likely increasingly focused on a Plan B of fostering collective European deterrence, it will continue to extend its hand to America and, if other attempts fail, prepare ground for a possible exploration of détente with Russia. This balancing act will require a permanently heightened level of defence spending, considerable diplomatic dexterity, and a willingness to question received wisdom. After a short interlude, history has returned to Helsinki.

© Matti Pesu and Tomas Wallenius, 2025, published by RUSI with permission of the author.

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