Finland successfully joined in April 2023. Sweden's candidacy stalled due to a strong pressure from Turkey, which demanded that Stockholm, known for its generous asylum policies, crack down on Kurdish militants campaigning against Ankara.
Turkish President Recep Tayyip Erdogan later demanded action after protesters insulted the Quran, Islam's holy book, while enjoying Swedish laws on freedom of expression.
In an apparent but unstated sweetness, the United States dangled the possibility of F-16 warplanes to Turkey, which has faced the wrath of US sanctions over a major military purchase from Russia.
In January, the Biden administration approved $23 billion in F-16 warplanes to Turkey following Sweden's membership confirmation.
The United States also forwarded $8.6 billion worth of more advanced F-35 jets to Greece, a fellow NATO member that has a historic rivalry and frequent tensions with Turkey.