TALLINN, Estonia — Late last month, Estonia’s foreign minister, Eva-Maria Liimets, flew into Kyiv to join her counterparts from fellow Baltic nations in an expression of solidarity with Ukraine as tensions mounted with Russia.

Like Ukraine, the three Baltic states — Latvia, Lithuania and Estonia — were once part of the Soviet Union. Unlike Ukraine, they had joined NATO in the early 2000s, and now enjoy the protection the alliance’s mutual defense guarantee provides.

After she arrived, Liimets, a soft-spoken career diplomat, took a walk around central Kyiv’s cobblestone streets in the cold night air. A tense calm suffused the city.

Early the next morning, a little before 6 a.m. on Feb. 24, Estonia’s ambassador in Ukraine called her with an urgent message: President Vladimir Putin’s invasion had begun. Like it was for millions in Ukraine — where the airspace was now closed and roads were quickly jammed by people trying to flee — the stakes of the slow-building showdown with Russia were suddenly stark.

Within minutes, Liimets packed her bags and was on her way to Estonia’s nearby embassy, and then, escorted by Ukrainian security, in a convoy headed west toward the Polish border. As they navigated droves of fleeing residents — it took more than four hours to get out of Kyiv — she could hear the sound of distant shelling.

As Russia presses its invasion deeper into Ukraine, Baltic leaders say the world has finally awakened to the admonitions they have been making for years: that Putin is prepared to use force, like he did in Georgia, Crimea and eastern Ukraine, to advance his political goals.

“Unfortunately, we were right,” Liimets said in an interview. Putin’s action in Ukraine, she said, “shows that Russia has not felt enough international pressure and they could continue with their ... plan to invade one of their neighboring countries.”

As the global implications of Putin’s assault set in, Baltic nations’ appeals for greater deterrence are translating into additional troop and aircraft deployments. Already in recent months, new NATO and U.S. forces have been dispatched to the region. In Estonia, a British-led force of some 2,500 NATO troops conducts training and exercises with local forces. Additional NATO forces are there for the Baltic air policing mission, which now includes American F-35s and British and U.S. F-16s. There are also American F-35s in Lithuania.

Such forces provide valuable reassurance for a country like Estonia, which has an active-duty force of 4,000 troops, and no combat aircraft.

At the same time, the region’s leaders are urging the bloc to do even more to bolster deterrence along its exposed eastern flank by abandoning a decades-old prohibition on permanent NATO basing there. They also want an expansion of the “air policing” mission over the Baltic Sea and the placement of NATO air defense systems, like Romania and Poland already have.

Lithuanian President Gitanas Nauseda issued a stark warning this month, saying that Putin “will not stop in Ukraine.”

The NATO reinforcements come after years in which Baltic officials say their fears were dismissed by much of Europe as paranoia or some kind of post-Soviet stress disorder. Even after Russia launched the first state-on-state cyberattack in 2007, a digital assault on Estonia over its decision to relocate a Soviet-era monument, NATO’s military planners moved slowly, only drawing up detailed defense plans for the region after Russia’s annexation of Crimea in 2014.

Across the Baltic countries, residents are showing their support for Ukraine, hanging blue-and-yellow flags and protesting outside Russian embassies, and taking what action they can to push back against Putin.

In Lithuania, a volunteer corps of online “elves,” including at least one member of Parliament, methodically debunks and derides Russian trolls and bots. Others post five-star reviews of Russian hotels and restaurants merely as a way of including photographs and data about Russian attacks on Ukrainian civilians. A popular app automatically connects users to one of 40 million randomly generated Russian phone numbers and provides tips on starting a conversation about Ukraine when the call is answered.

“Our biggest weapon is that we understand the Russians and we speak their language,” said Aleksandra Ketleriene, 34, an online reporter for the national broadcasting service.

A large portion of the region’s population still remembers the Soviet occupation, which ended in 1991. During the decades of Soviet rule, the Kremlin lured ethnic Russians to the Baltics by giving them better jobs and better housing than the local population, the most rebellious of whom they sent to prison camps in Siberia. Russians who were left behind when the Soviet Union collapsed, especially in Latvia and Estonia, posed a challenge for local policymakers, who faced the difficulty of integrating large populations who looked to Russia as their political and cultural homeland.

“The Ukrainians are fighting for us,” said Dainius Navikas, a management consultant in Vilnius, the Lithuanian capital. Last week, he donated a vehicle to be converted to military use and delivered to Ukrainian fighters as part of a private aid campaign that has already netted more than 17 million euros from Lithuania’s 2.8 million citizens. “If they lose, we could be next.”

Others are making preparations for what they fear might be an eventual Russian assault. At social gatherings in Riga, the capital of Latvia, young families are swapping details of their plans to evacuate further west should it become necessary. Some are laying backup plans for their children to leave the country without them if need be. In the Estonian capital, Tallinn, residents are checking their basements in case they need to use them as shelters. In the university town of Tartu, one grocery store’s shelves were empty of iodine, the solution that protects against radiation exposure after a nuclear attack.

“So far we are not being threatened, as far as I understand,” said Dima Golubevs, a 40-year-old Latvian video producer at a recent protest outside Russia’s embassy in Riga. But he noted that he was still a tiny bit nervous about whether NATO would come to the aid of Latvia in the event of a Russian invasion.

“I can say 99% I feel safe,” Golubevs said. “But 1% is still a lot.”

Even as European leaders show a united front in support of Ukraine, some Baltic officials feel a more urgent threat to their security than do other NATO nations. Last week, Lithuania’s Parliament approved a resolution calling for a no-fly zone over Ukraine, a step that the United States and other NATO leaders have said they will not take because it could trigger war with Russia.

While Baltic nations want to support Ukraine, officials also feel constrained in the military aid they can supply to Ukraine, mindful of the need to keep weaponry in reserve in case they need it themselves.

More than a frontal attack on NATO, some officials worry about the possibility that Putin could launch a smaller maneuver to show that NATO is weak — for example, seizing an island off the coast of Estonia — or renew hybrid warfare, like the cyberattacks that struck Estonia in 2007.

“If he wins in Ukraine, it will legitimize war for him” as a way to achieve his goals with other countries, said one Baltic official who spoke on the condition of anonymity to discuss the matter frankly.

Despite the stepped-up defenses, there is also concern that the West might relax its resolve, either due to a negotiated settlement between Ukraine and Russia or because of the high cost of economic sanctions on Russia — with potentially problematic results in Eastern Europe.

“My biggest fear is that the minute there is the slightest concession from Russia, countries will rush to lift these sanctions,” said Toomas Ilves, who served as Estonia’s president from 2006 to 2016.

While the world may now share the Baltics’ perspective more than ever before, Ilves said, “there is little joy in being right.”

Birnbaum reported from Washington, Sonne reported from Riga, Latvia, and Hendrix reported from Vilnius, Lithuania.

previous coverage

• US and NATO allies prepare ideas for strengthening defenses in countries closer to Russia
• Pentagon likely to look eastward if it brings US Army tanks back to Europe
• Spending bill boosts funding to troops, military families and weapons
• US has 100,000 troops in Europe for first time since 2005

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