The about-face comes after months of arduous negotiations over Turkey’s demands and on the eve of a critical two-day NATO summit where leaders including US President Joe Biden are eager to show a united front and signal to Vladimir Putin that his war on Ukraine has only strengthened the alliance.

NATO’s northern enlargement heralds one of the most prominent changes in the European security landscape after Russia’s aggression led to shifts including a ramp-up of defense spending in Germany and plans to bring back conscription in France. The early 2022 attack on Ukraine prompted an almost overnight change in public opposition to membership in NATO in Finland and Sweden.

“Completing Sweden’s accession to NATO is a historic step that benefits the security of all NATO allies at this critical time,” Stoltenberg said in Vilnius. “I will not give you the exact dates for that. But this is a clear commitment.”

Eoin Treacy's view

The big question for defense companies is where will the money come from for countries to meet their NATO spending targets? The need is clear, but the route to additional spending runs through national priorities like pensions and social programs.