NATO Will Need a Transition Plan If Finland, Sweden Ask to Join

The prime ministers of Finland and Sweden have indicated that Vladimir Putin’s unprovoked and brutal attack on Ukraine is shifting the political balance in both nations in favor of both countries applying for NATO membership. They have seen in Ukraine that countries without an Article 5 collective defense pledge are vulnerable. The choice must be theirs to make, with no pressure from NATO members.

Should they make the sovereign decision to apply for NATO membership, the period between their application and final approval by all NATO members, including legislative action, may be difficult. Putin will do whatever he can to threaten the applicant countries directly and derail the process more broadly. The Kremlin has already warned of a military response including the deployment of nuclear and hypersonic weapons to the Baltic Sea area if either nation should decide to apply. (Lithuania was quick to point out that Russia already stores nuclear weapons in the Kaliningrad exclave.) Thus, if they decide to apply for membership, Finland and Sweden should work with Alliance countries to design a transition plan to protect them during the interim period.

A jointly developed transition plan might have several related elements. 

The Alliance would need to expedite its acceptance process for these two NATO partners. Under Article 10 of the Washington Treaty, all 30 NATO nations must approve new members, which in the past has taken up to two years. Traditional preliminary steps like an Intensified Dialogue and a Membership Action Plan would be unnecessary given the high degree of military interoperability that already exists between NATO and these two advanced nations. NATO Secretary General Jens Stoltenberg, who has already expressed support for their application, should design mechanisms to encourage rapid approval. Because Putin will press individual NATO nations to drag their feet, counter actions need to be taken.

The United States could set an example in this expedited acceptance process by seeking rapid Senate ratification. The merits of NATO enlargement have already been widely debated. Strong bipartisan Senate support should exist. President Joe Biden might begin this process with a forceful speech noting that both nations are Western democracies that are serious about defense and already operate militarily together with NATO. Finland spends about 2 percent of its GDP on defense and has an impressive comprehensive security concept of the kind that has worked well for Ukraine. Swedish defense spending is lower but rising, and it has an impressive defense industry. Together these two nations fill a strategic geographic gap along the Alliance’s border with Russia. 

Interim security guarantees might prove necessary as Russian pressure mounts. Both nations are European Union members and thus covered by Article 42.7 of its Lisbon Treaty which obliges all members to “aid and assist by all means” in the case of armed aggression. The EU might reinforce this obligation by noting officially that during the interim the commitment would be seen as the EU equivalent to Article 5 of the NATO treaty. 

Other steps might be taken to strengthen interim security guarantees. For example, the United States through presidential statement, joint resolution, or even a clause in the Senate instrument of ratification could extend interim security guarantees. The Northern Group and the Nordic-Baltic Eight Group, both of which include Finland and Sweden, might consider strengthening interim commitments.

Given Russia’s current military invasion of Ukraine, Moscow is unlikely to shift a large number of ground forces to the Baltic region. But if they do shift forces, several options exist for countervailing measures. Given both nations’ involvement in the British-led Joint Expeditionary Force, moving some element of the JEF forward might be attractive. Both nations have also participated in the NATO Response Force, which is already on high alert and ready for deployment. In extremes, American ground forces would also be available. Naval and air deployments should also be considered including for Baltic Sea naval exercises and a Nordic-Baltic area air defense zone, as Russian air and naval forces are more available for redeployment. Such conventional force deployments also could constitute a response to additional nuclear threats by Putin.

Another option which could be enacted very soon is to expedite defense cooperation under the 2018 trilateral Finnish-Swedish-U.S. defense cooperation agreement called the “Statement of Intent.” Actions could range from enhancing strategic planning; accelerating arms transfers; strengthening intelligence, surveillance, and reconnaissance cooperation; and adding multilateral exercises.

Finally, consideration might be given in this plan to defusing some of Russia’s concerns. For example, Finland could theoretically control naval passage to Saint Petersburg, and it is close geographically (as is NATO member Norway) to Russia’s nuclear and naval bastions on the Kola Peninsula. Assurances might be designed to reduce Russian fears in these areas, as long as any such confidence-building measures are reciprocal. In no case should any such assurances make Finland and Sweden second-tier NATO members with undue restrictions on force deployments. 

NATO should also be ready to explain why rapid acceptance of Finland and Sweden is warranted while several NATO members are unwilling to accept Ukrainian membership. Principal reasons include that both nations are EU members while Ukraine is not, and that Article 10 of the Washington Treaty states new members must “contribute to the security of the North Atlantic area” which is difficult for Kyiv to do while partially occupied by Russian troops. 

Hans Binnendijk is a distinguished fellow at the Atlantic Council. He has served as director of NDU’s Institute for National Strategic Studies and as NSC senior director for defense policy and arms control.

Barry Pavel is senior vice president at the Atlantic Council and director of the Scowcroft Center for Strategy and Security. He has served as NSC senior director for defense policy and strategy.