What to Know About How to Join NATO

Finland and Sweden applied to join NATO in May 2022.

Posted June 8, 2022

Sweden and Finland have applied to join NATO. Their requests came nearly three months after Russia first invaded Ukraine and marked a turn away from both nations’ official stances of neutrality, which they adopted after World War II.

Faculty in the Sam Nunn School of International Affairs explained what the process of joining NATO — also known as accession — looks like, as well as the implications of adding two new countries to the Western defense alliance. Russian President Vladimir Putin has warned of further military action if NATO grows stronger. Meanwhile, NATO member Turkey has expressed reservations about the two countries joining, as well.

The Accession Process

Robert Bell is a distinguished professor of the practice in the Nunn School and has served in several positions in and around the alliance, including as the defense advisor to the U.S. ambassador to NATO.

The next step in the accession process, Bell explains, is for NATO Secretary-General Jens Stoltenberg to informally consult with the 30 current alliance members on their preferences. If he finds consensus in favor of them joining, he will provide Finland and Sweden with formal invitations to do so.

After the applicant countries accepted such an invitation, the NATO legal advisor would draft two protocols in conjunction with the 1949 Washington Treaty that would allow each country to become a member. The protocols would then be sent to the 30 current allies for them to ratify. If even one country said no, Finland’s and Sweden’s applications would fail.

Bell notes that in the United States, protocols must be ratified with two-thirds of the Senate, or 67 members, voting in favor. Shortly after Finland and Sweden submitted their official requests to join NATO, more than 80 senators called for quick approval of the applications. President Joe Biden also has stated his support for the two countries joining the alliance.

If all NATO allies ratified the protocols, Sweden and Finland would become members. In the meantime, Bell says that they could still attend meetings as “invitees,” where they could speak and listen but not vote.

Roadblocks to Unanimous Ratification

Despite strong support from the United States, Finland’s and Sweden’s confirmations are not a foregone conclusion. Turkish President Recep Tayyip Erdoğan has expressed reservations about the two countries joining NATO. He claims the two countries harbor members of several groups that Turkey deems terrorists, namely Kurdish separatist groups.

Because accession requires unanimous consent from NATO allies, Turkey could veto both applications.

Bell argues that Erdoğan has multiple goals in mind by threatening to veto the applications, but that Turkey will agree to ratify the protocols in the end. While the Turkish president primarily wants Finland and Sweden to crack down on Kurdish separatist organizations within their borders, Bell believes that he also wants the U.S. Congress to authorize additional military aircraft sales to Turkey. Finally, Erdoğan also could want to remind other NATO allies never to take Turkey’s consent for granted, says Bell.

Margaret E. Kosal, associate professor in the Nunn School, agrees that Erdoğan’s hesitance does not mean that the bids are already doomed. She also feels the president is using this opportunity to gain ground on issues important to Turkey as he comes up on an election year in 2023.

“It’s frustrating that Erdoğan is ‘playing politics’ with NATO at this time, but it’s also politics,” Kosal said. “Negotiating will require skilled diplomacy, which illustrates just how valuable experienced diplomats are to advancing the national interests of the U.S. and our allies. Diplomacy is not a sport for amateurs.”

Kosal, alongside other faculty members in the Nunn School, teaches courses that cover several aspects of diplomacy. Related courses for the Fall 2022 semester include INTA 2221: Politics of the European Union and INTA 3110: U.S. Foreign Policy. The Nunn School also offers research programs in international security, as well as in international affairs, science, and technology.

Retired Gen. Philip Breedlove, former supreme allied commander Europe of NATO and a distinguished professor of the practice in the Nunn School, compares Erdoğan’s tactics to something familiar to him from his days as a Georgia Tech engineering student: a fulcrum.

“Turkey is a country of incredibly adept diplomats, and Erdoğan is, in this case, using Finland’s and Sweden’s applications as a simple machine,” Breedlove explained. “The applications are the fulcrum, and he’s using them to lift up Turkey’s national interests without having to do as much work on his own.”                                                                                    

A New NATO

All three Nunn School faculty members believe that if Finland and Sweden are allowed to join NATO, the alliance will grow stronger because of the two countries’ defense capabilities and positions in northern Europe. Bell notes the irony in that one of Putin’s main goals for invading Ukraine was weakening NATO, and now, the opposite could happen.

Breedlove emphasizes that these two specific countries could boost the Western defense alliance because of their military strengths and familiarity with how NATO operates.

“Both Sweden and Finland have worked closely with NATO in the past, and they will be able to provide modern, effective military capabilities almost immediately if they are accepted as members,” he said.

Bell and Kosal also agree that while Putin has threatened military action in response to a growing NATO, that should not deter the alliance from acting to confirm Finland and Sweden as members. Kosal and Bell note that Putin walked back previous threats of military action in response to NATO expansion. He more recently has said that he would only respond if NATO went on to increase its military presence near Russia.

“Yes, threats by Putin must be taken seriously,” Kosal said. “However, that does not mean that the U.S. and NATO should act solely — or even as one of the leading factors in consideration — based on Putin’s threats. We can see that he’s playing a weak hand because of how he has adjusted threats regarding Sweden and Finland joining NATO.”

Three other countries have outstanding NATO applications: Bosnia and Herzegovina, Georgia, and Ukraine. Bell says that their requests to join have not moved forward because one or more members are not willing to accept them into the alliance.

As the war in Ukraine continues and Western defense architecture shifts, Bell stresses the importance of young people — particularly students interested in international affairs — paying attention to new developments.

“It is important for students to closely follow international affairs now because several of the crises extant in today’s world affect their lives most directly. For example, climate change affects us all,” he said. “Russia’s war against Ukraine threatens the world’s food supply, elevates the costs of energy, and threatens to give solace to those nations that would flout the international rules-based order through aggression and military force.”

Contact For More Information

Grace Wyner

Communications Officer

Sam Nunn School of International Affairs | School of Public Policy