Why Sweden’s Path to NATO Membership Has Been So Rocky

NATO’s 31 member states assembled on Tuesday in Vilnius, Lithuania, for the defense alliance’s annual summit. But the biggest news of this year’s NATO summit may be what took place in the lead up to it.

After hours of talks with Swedish Prime Minister Ulf Kristersson and NATO Secretary-General Jens Stoltenberg on Monday, Turkey’s President Recep Tayyip Erdoğan agreed to lift his veto of Sweden’s NATO membership bid. His U-turn comes after Stockholm reaffirmed its support behind for Turkey’s longstanding bid to join the E.U., and, some have speculated, Washington’s announcement on Tuesday that it “intends to move forward” with the transfer of F-16 fighter jets to Turkey.

“Sweden will become a full member of the alliance,” Stoltenberg said of the decision on Monday. He added that Erdoğan had made a “clear commitment” on Sweden’s accession.

Here’s everything you need to know about Sweden’s rocky NATO membership bid.

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Why is Sweden not already a NATO member?

For over 200 years, Sweden has had a long history of military non-alignment that was shaped by the end of the Napoleonic Wars, which saw the country break diplomatic ties with France and permit the U.K. to use Swedish Pomerania as a military base. Napoleon prompted Russia and Denmark to declare war on Sweden, which ultimately lost to the powerful coalition. “Sweden had to withdraw from Northern Europe’s power politics around 1809. We got a new French king, Bernadotte, and we withdrew because we were too weakened,” Anna Wieslander, director for Northern Europe at the Atlantic Council, tells TIME. “Since then, we have kept that stance but it was never treaty bound for Sweden. It was always about navigating and maneuvering in European politics.”

Read More: Finland and Sweden Seem Likely to Join NATO. What That Means for Europe

When Sweden joined the E.U. in 1995, Wieslander says the country formally dropped neutrality but retained some characteristics of the tradition. “When you’re a member of the European Union, you cannot really be neutral because it’s a political alliance,” she says.

Then, after Russia’s full-scale invasion of Ukraine last year, public opinion in Sweden shifted in favor of joining NATO. A Gallup poll published in September of that year found that 74% of Swedes supported the country joining NATO.

Why was Erdoğan holding up Sweden’s NATO membership bid?

While Finland’s membership was ratified by all member states in April, Erdoğan blocked Sweden’s bid, accusing the country of harboring Kurdish exiles affiliated with the separatist Kurdistan Workers’ Party (PKK), which Turkey, the United States, and the European Union consider a terrorist group.

Erdoğan had also withheld his support over concerns over Quran burning in Sweden. “We have made it clear that the determined fight against terrorist organizations and Islamophobia are our red line,” Erdoğan said, after a cabinet meeting last week. “Everyone must accept that Turkey’s friendship cannot be won by supporting terrorism or by making space for terrorists.”

What concessions did Turkey secure?

With the trilateral memorandum reached by the leaders of Turkey, Finland, and Sweden at last year’s NATO summit in Madrid, the three countries agreed on areas to work on to secure Sweden’s entry. Among Turkey’s requests were arms deliveries, stronger anti-terrorism legislation, and more collaboration on extradition requests. Wieslander says Sweden has met these requests head on, notably tightening anti-terrorism legislation in June 2022.

Earlier this month, Sweden’s justice minister also said the government could be open to amending its laws around Quran burning, after one such incident on Eid al-Adha drew protests in several Muslim-majority countries. “It is clear that we must analyze the legal situation in the light of the spring events and those judgments. The analyses are ongoing and we will come back with any conclusions,” Gunnar Strömmer told the Swedish newspaper Aftonbladet, according to Euronews.

Following Erdoğan’s U-turn on Sweden, NATO’s Stoltenberg said on Monday that “Sweden agreed today as an E.U. member was to support actively efforts to reinvigorate Turkey’s E.U. accession process.” But he added that the matter was “not an issue for NATI, it is an issue for the European Union.”

The Biden administration has also been careful not to directly link the decision to send F-16 fighter jets to Erdoğan’s U-turn on Monday.

What happens next?

It’s unclear how long the process of Sweden’s NATO’s accession could take from here. According to NATO convention, membership is only valid once every member of the alliance has signed and ratified the Accession Protocol.

When asked about these practicalities, Stoltenberg said on Monday it is “not for me to go into the details of the timelines of the different political institutions in Turkey.”

Nevertheless, experts say news of Sweden’s accession will likely increase the security of the whole NATO alliance and allow for greater military collaboration and operational planning.

“When you have disagreement on which allies to include in NATO, that weakens NATO politically and benefits Russia,” says Wieslander.