Sweden Joining NATO Is a Nightmare for Russia's Baltic Sea Fleet

Russia's Baltic Sea fleet has a "serious problem" on its hands as NATO prepares to expand into Sweden, experts have told Newsweek.

NATO's dominance of the Baltic Sea, surrounding Moscow's naval bases in the Russian exclave of Kaliningrad and in the country's second-largest city, St Petersburg, is set to strengthen with Sweden joining the alliance.

But the soon-to-be NATO addition presents military challenges to Russian forces in the Baltic, experts say, as Moscow stares down what has come to be dubbed a "NATO lake."

Spurred on by Russia's invasion of Ukraine, Finland joined NATO in April 2023, with Sweden shortly expected to follow. Russian President Vladimir Putin has previously spoken out against both Finland and Sweden joining NATO, warning of "serious military and political consequences."

On Monday, Turkish President Recep Tayyip Erdoğan reeled in his opposition to Stockholm's NATO membership in exchange for Turkey's chances of joining the European Union being revived, marking the next step towards Sweden's accession to the military alliance.

NATO will be more able to dominate the Baltic Sea not just on and under the surface, but through airpower, Frederik Mertens, a strategic analyst with the Hague Center for Strategic Studies told Newsweek. "In this field, NATO already has an overwhelming advantage," he said, adding: "Russia's Baltic fleet has a serious problem."

Faced with NATO's airpower, bolstered by Sweden, Russia's surface ships will need to rely on ground-based air defenses, he argued.

Not only that, NATO's ability to control the environment in the Baltic Sea means there "hardly is a spot of the Baltic left where a Russian surface ship cannot expect the imminent attack of an advanced sea-skimming missile," Mertens said.

Once Sweden is a member, Stockholm will be more closely integrated into NATO in several ways, including through information and intelligence sharing, according to Dmitry Gorenburg, a senior research scientist with the Center for Naval Analyses. Russia will likely be concerned that foreign troops—notably U.S. soldiers—could populate NATO bases in the country, he told Newsweek.

Sweden itself brings its own considerable force to the alliance, particularly through its submarine fleet, Mertens added. The Swedish navy "will bring an enormous amount of surface capability to us in the Baltic Sea," Gen. Christopher Cavoli, who heads U.S. Army forces in Europe, told lawmakers in May 2022. "They also have underwater capabilities that will help us as well," Cavoli said.

But NATO countries could also use sea mines to hem in Russian vessels, and would be a key weapon against Moscow in the region in the case of conflict, Mertens said. Russia's ability to deny or control how NATO forces deploy resources in the Baltic, and Moscow's land and air forces in the region, are perhaps more under threat than the Baltic fleet, according to Mertens.

Estonian Foreign Minister Margus Tsahkna told Newsweek recently that he could not "see any serious arguments against the Swedish membership of NATO," adding it "is very politically important that you have neighboring countries as big as Finland and Sweden, and powerful as they are, in the same alliance."

"This is tremendously important that the Baltic Sea is now a 'NATO lake,'" he said. "Everybody who understands anything about defense understands that this is changing a lot in strategic ways," Tsakhna said.

Newsweek has reached out to the Russian Defense Ministry for comment via email.