After more than 200 years of neutrality since the end of the Napoleonic Wars, Sweden's national flag was raised at the headquarters of the North Atlantic Treaty Organization (NATO) on Monday (March 11) as the alliance's 32nd member in response to Russia's invasion of Ukraine in 2022.

Despite steady rain, Swedish Prime Minister Ulf Kristersson, Swedish Crown Princess Victoria, and NATO Secretary-General Jens Stoltenberg witnessed the raising of the flag among the official circle of national flags at the alliance's headquarters in Brussels.

"The Russian, brutal, full-scale invasion against Ukraine united Sweden behind the conclusion that a full-fledged NATO membership is the only reasonable choice," Kristersson said. "We are humble, but we are also proud. We know the expectations for Sweden are high, but we also have high expectations for ourselves."

In a show of national unity, Swedish government ministers and party leaders from across the country's political spectrum also attended in a show of national unity, the Associated Press reported.

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Nordics as NATO Region

While neutral, Sweden has strengthened its defensive capabilities to become self-sufficient, especially after the Second World War and the Cold War. A similar military nonalignment has also been practiced by neighboring Finland, which also applied for NATO membership alongside Sweden after the Russian attack on Ukraine.

Finland already joined in April 2023. The country's defense ministry welcomed "our brothers and sisters in arms" in a post on X, formerly Twitter.

"[N]ow we stand at the beginning of a new era," the ministry added. "Together and with other allies in peace, in crisis and beyond."

Stoltenberg also called out Russian President Vladimir Putin for launching the war in Ukraine, perceiving that NATO was expanding eastward. However, the war had an adverse effect, as it pushed more countries to join the alliance.

"When President Putin launched his full-scale invasion two years ago, he wanted less NATO, and more control over his neighbors. He wanted to destroy Ukraine as a sovereign state, but he failed," he said during the ceremony. "NATO is now bigger and stronger. Ukraine is closer to NATO than ever before, and as the brave Ukrainians continue to fight for their freedom, we stand by their side."

With Sweden officially part of NATO, the alliance has completed a strategic ring of territory around the Baltic Sea, and the country could now benefit from Article 5, the treaty's collective security guarantee vowing that an attack on one member nation would mean an attack on all.

Before the ceremony, Sweden and other Nordic nations joined the NATO military exercise called Stalwart Defender 24, which saw up to 90,000 troops participating in the training event.

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