Sweden's First Task in NATO: Defend Key Island on Baltic's Sea Lanes

U.S. Marines go ashore in an exercise on the island of Gotland, 2023 (U.S. Navy)

The government of Sweden is looking at ways to reinforce the garrison on Gotland, the strategically-located island in the center of the Baltic Sea. Gotland is critical for the control of the sea lanes in the region, and it gives Sweden - and its new NATO allies - a profound advantage in securing the waters and the airspace off Poland, Latvia, Lithuania and Estonia. In Europe's current security environment, holding and defending Gotland is more important than ever for the Swedish government.

Sweden applied to join NATO last year in the wake of the Russian invasion of Ukraine, ending two centuries of neutrality. It secured the final vote of approval to join the alliance last week, and strengthening the defense of Gotland is the first order of business. It "is one obvious thing to be discussed with our new NATO allies," Swedish Prime Minister Ulf Kristersson told the Financial Times this week.

"Everything to do with the Baltic Sea is such an obvious candidate," Kristersson added. "That goes in terms of presence on Gotland, but also in terms of surveillance, in terms of submarine capabilities."

As recently as the 1990s, the garrison on Gotland numbered some 25,000 soldiers, but the numbers were drawn down to zero in the years that followed as relations with post-Soviet Russia improved. The Swedish government decided to redeploy a small regimental unit to the island in 2016-18, and it allocated further resources in 2022-23.

Gotland is just as important to NATO as it is to Sweden. If Russia ever decides to re-absorb Latvia, Lithuania and Estonia, as it did in the Soviet era, Western war planners believe that Gotland would be an early target. Capturing the island would give Russia an "unsinkable aircraft carrier" large enough to base anti-ship and anti-aircraft missile systems. This would complicate sea and air access for NATO forces and interfere with efforts to reinforce the Baltic states.

"I do not think there is any island anywhere that is more important," said Gen. Ben Hodges, then-commander of U.S. Army Forces Europe, in a visit to the garrison in 2017.

Sweden may be able to call on U.S. capabilities to build up Gotland's defenses. Under a recently-inked cooperation agreement, the U.S. military has usage and access rights to more than a dozen base sites around Sweden, including two areas near the port of Visby, Gotland.