Finland has always been a target for hybrid threats from Moscow, and now it's gearing up for more. "We already knew that the red line for the Russians was our accession to NATO," said Juha Martelius, the Finnish Defense Ministry's deputy director general for defense policy. "We are waiting for some kind of reaction" after the blue-and-white Finnish flag was raised outside NATO headquarters on April 4.

No one thinks the new 200-kilometer (124-mile) fence Finland has started building along its eastern border would prevent a military incursion from Russia. But that's not why the government decided last year to construct it and enhance surveillance capacity along the route.

In the past several years, every European Union and NATO country bordering Russia or Belarus has been subjected to large influxes of asylum-seekers orchestrated by Moscow. Latvia, Lithuania and Poland saw the worst of it in 2021, but it also happened in 2015 and 2016 at border crossings in Finnish Lapland. Finland is the last of these nations to decide to construct a physical barrier.

'Year Zero' starts now

While the war in Ukraine wasn't the impetus, it definitely reinforced the decision. "We've seen what Russia has done in Ukraine, so anything is possible," Martelius explained. "After that, people realized this is 'year zero' for our new relationship with the Russians. It doesn't matter what kind of end result will take place in Ukraine: We will have a totally different relationship with the Russians than we had before."

In Imatra, the city nearest to where the fence project is kicking off, Mayor Matias Hilden says no one is enthusiastic about the project, but they're resigned to it. "It's a little bit sad that we need it," he told DW in an interview in Imatra City Hall.

He explains that a decade ago, no one thought twice about hearing Russian spoken in stores or spas and Russian license-plated cars were ubiquitous in the streets of the city, just 7 kilometers (4.4 miles) from the border. "Russians used to buy almost every second property" in the area at that time, he explained, while day-trippers meant a reliable income for Imatra's shops. Some of those businesses already had to close when COVID cut off travel, the mayor said, with a ban on Russian tourists due to sanctions over Ukraine being the knockout blow for others.

Now, hearing Russian around town would definitely cause a second — suspicious — glance, Hilden believes, and no one's counting on the return of friendly relations anytime soon. "It's good to prepare for the sort of threats that are probably going to happen in the future," he added.

One long-time resident of Imatra, William Dennisuk, said he knows people with an even stronger sense of foreboding that stretches all the way to scenarios of military invasions. "It's clear people are nervous," he said, describing the way friends "who had very clear plans and no worry about the future here [are thinking], 'Maybe I'll put that off for a year and see how things go,' because do you want to invest and put a lot of money into something and then within a year or so see that it's under somebody else's control?"

He mentioned the Donbas region of Ukraine, much of which is currently occupied by Russia, as an example of where the Kremlin used a high population of Russian-speaking residents as an excuse to invade.

Border Guard: 'We have to be ready'

While that might seem an extreme scenario to imagine in Finland at the moment, the concern came up with the Defense Ministry's Juha Martelius as well. Before the Ukraine war, he noted, "we knew that Russia was willing to use military force in some extreme cases. Now we know Russia is willing to use military force in cases that don't seem to be extreme."

Up in the woods that are being cleared to make way for the fence, Colonel Mika Rytkonen, a commander in the Finnish Border Guard, emphasized that there are no indications Russia is planning to launch any kind of major attacks on Finland in what he called a "very short, short time."

But, he added, "Does anybody know what Russia will do in the future? At least I don't. We have to be ready."

Edited by: Timothy Jones