NATO prepares Baltic fortress to counter Putin

NATO is trying to fortify a windswept Baltic island that military planners increasingly see as one of the alliance's most exposed — and strategically vital — front lines against Russia.

Located in the middle of the Baltic Sea, Gotland is just 300 kilometers from Russia's heavily militarized enclave, Kaliningrad.

As fears grow about Russian aggression, hybrid attacks and the US's wavering commitment to European security, Sweden and its NATO allies are racing to turn Gotland back into a military fortress.

Last week, Sweden completed its first NATO-coordinated exercise on the island since joining the alliance in 2024. Some 18,000 troops from 13 countries trained on the dusty fields of Gotland for a possible Russian attack.

A Russian attack “could happen at any time,” Swedish Defense Chief Michael Claesson told POLITICO, as soldiers wandered among armored vehicles on the western side of the island.

The exercise highlighted the difficulties Sweden faced: The US scaled back its participation – part of a broader pattern as Donald Trump withdraws from NATO – and Ukrainian troops taking part in the exercise showed off their drone warfare prowess by swiftly destroying a Swedish armored detachment.

Then there is the need to calibrate a response to Russia's covert hybrid attacks that fall short of a full-scale war.

“They’ve seen a lot of increased Russian activity … cable cutting, drone flights, quite a few espionage incidents,” said Anna Wieslander, director for Northern Europe at the Atlantic Council think tank. “When you have a situation where you have a lot of uncertainty about U.S. engagement … the risk increases that Russia will see this as an opportunity.”

Bottomless aircraft carrier

Variously changing hands between Denmark, Sweden – and briefly Russia – Gotland is an important strategic asset.

“With the range and positioning of today’s [weapons] systems, if you control Gotland, you can control a lot of what’s happening in the Baltic Sea,” said Niklas Granholm, a deputy director of the government-backed Swedish Defence Research Agency.

The island has been called a bottomless aircraft carrier for its role as a critical launch pad for air operations across the region; fighter jets taking off from there can reach any Baltic capital “within minutes,” he said.

If Russia took the island and installed air defense systems, it could block ships and planes supplying the three Baltic states and Finland, he argued, and hinder reinforcements of Allied troops.

If NATO holds Gotland, it can close off Moscow's access to the Baltic Sea, use longer-range missiles to defend the region, and fire munitions deep inside Russia.

In response to the Russian threat, Stockholm is rapidly remilitarizing the island of 60,000 people – reversing a post-Cold War withdrawal that left only a handful of troops on Gotland.

Sweden has invested over 200 million euros in infrastructure improvements, reactivated air defense systems, and re-established a regiment armed with CV90 armored vehicles and Leopard 2 tanks.

Andreas Gustafsson, the commander of the Gotland Regiment, said that "at least a thousand more troops" would join the 4,500 troops currently on the island "within a year" on a rotational basis.

He added that he hoped long-range artillery units would join them “quite quickly.” The island is also expected to receive new medium-range IRIS-T air defense systems by 2028.

One possible scenario was that Russia would try to secretly land troops on the island from a merchant ship while jamming radio signals and suppressing air defenses with drones, Wieslander said.

Despite these concerns, Gotland's security is now in a "good position," she added, especially after Sweden joined NATO in 2024.

The exercise was intended to test multinational cooperation – bringing together Canadian and Danish soldiers, Finnish F-18 fighter jets, British snipers, US and Norwegian marines and Dutch Apache helicopters.

Sweden's membership in the alliance means "we have redesigned our plans," said French Rear Admiral Frédéric de Rupilly, NATO's deputy chief of staff for plans at the alliance's joint command in Virginia.

The void on Gotland

In addition to preparations for a direct Russian attack, Gotland is facing increasing hybrid threats from Moscow.

In the past 18 months, the island experienced a sudden water leak after a critical pump was sabotaged, faced a cut in an underwater fiber optic cable, and has seen frequent radio interference affecting everything from airplanes to ambulances.

Claesson, the army chief, said he was “quite concerned” about hybrid attacks. “Obviously the Russian doctrine… is really to try to identify weaknesses and vulnerabilities and do everything they can to exploit them,” he added.

Like its NATO allies, Sweden must face the imminent prospect of fighting with less – or no – support from the US.

In the past month alone, Trump has stunned Europe by announcing sudden troop withdrawals from Germany and Poland, warning of further long-term reductions in capabilities, and undermining the alliance's credibility, raising further questions about Washington's credibility.

In a sign of this vacillation, the U.S. has reduced the number of troops it is sending to the Gotland exercise, according to a person familiar with the matter. A spokesman for U.S. Army Europe and Africa told Politico that “participation levels from different countries often vary during the planning phase,” noting that 300 U.S. soldiers still joined. They declined to say how many were originally planned.

For their part, American troops participating in the exercise insisted that military ties remain strong.

"Our forces have worked together extremely well," said Lieutenant Colonel Travis Chamberlain, commander of a US Marine battalion sent to Gotland.

“We have seen high levels of integration… working on very detailed security integration plans around how we will protect the force and provide logistical support across the island,” he said as his soldiers mingled with Swedish troops in a grassy enclosure.

As one of the largest defense spenders in NATO at 2.5 percent of GDP and with a strong domestic arms industry, Sweden "does not rely on the US to defend Gotland," Wieslander said.

But she said she needs Washington for certain weapons systems, including Patriot PAC-3 missiles, and logistical support such as equipment maintenance.

The exercise also highlighted the new era of massive drone strikes – something where Ukraine and Russia are far ahead of the alliance in terms of innovation and production capabilities.

Swedish troops were forced to restart part of the exercise three times after 17 Ukrainian soldiers deployed drones to annihilate their troops, according to a 24-year-old drone operator from central Ukraine, who went by the call sign Tarik.

“We had a mission with a scenario with… up to 20 battle tanks attacking in a mechanized attack,” he said, as a mounted, single-track attack drone flew over the rural horizon behind him.

"I just flew my drone - I saw them all, so they were easy targets," he said.

Preparing for more

Sweden – and NATO – insist they are working hard to address these problems.

After the recent hybrid attacks, Meit Fohlin, the head of the regional government, said she meets “every week” with the coast guard, police, firefighters, army, hospital, water and energy operators to draft responses for every possible scenario – from power outages to supply blockades to an armed attack on the local port.

"We have to be on top of everything," she said from her office in the island's medieval capital, Visby, adding that she is now working with all 92 parishes on the island to guide them on how to respond to any crisis scenario.

Gustafsson, the chief of the Gotland regiment, said he was drawing immediate lessons from the Ukrainian drone unit.

"I was quite surprised by the numbers they use and deal with every day," he said.

"My main conclusion is that we need to train a lot more with drones."

But given Gotland's importance to the alliance, some capitals still say NATO could do more.

The alliance should consider deploying permanent long-range air defense systems on Gotland to deter Russia, said two NATO diplomats, who were granted anonymity to speak freely.

The key is not to let Moscow take the initiative, Claesson said.

"We should not sit back and wait for this or that level of regeneration of the Russian armed forces to happen," said the Swedish defense chief, "but rather be constantly on alert and prepared."