Two years after Russia’s invasion of Ukraine, countries such as the Baltic states and Finland warn that a threat to their own territory may be just over the horizon, with some intelligence agencies saying the Kremlin could make such an attempt within a decade. Now they are taking lessons from their enemy’s robust defense lines in Ukraine, noting that Russia’s system of minefields, concertina wire and trenches made it all but impossible for Kyiv’s forces to advance last summer.
European states are still clamoring for F-35 fighter jets and space-age weapons, but the renewed interest and investment in century-old tactics is the latest example of how Russia’s war in Ukraine is upending long-held assumptions about how to defend NATO territory, with a revived focus on stopping tanks and mobile artillery. And though policymakers say they are still confident that NATO would come to their defense, they add that Trump’s rhetoric makes it more important than ever to be able to hold their own for as long as they can.
Nowhere have the choices been starker than in the discussion about land mines, as militaries weigh their low-cost ability to slow tanks and buy time for NATO rescuers against the risk to future generations of their own citizens. Land mines come in many forms, but the cheapest and simplest anti-personnel variant, once laid, can pose a hazard decades after a conflict ends. Mines and other explosive remnants of war killed or injured at least 12 civilians a day globally in 2022, many of them children, according to the Landmine and Cluster Munition Monitor.
Policymakers in all three Baltic nations — Lithuania, Latvia and Estonia — have had conversations in recent weeks about whether to pull out of the international convention that bans anti-personnel mines. For now, each has opted against it, but all are investing in antitank mines and other munitions that are less hazardous to civilians. It is a striking development in nations whose forests and fields still sometimes disgorge unexploded shells and ordnance from heavy fighting during World War I and World War II.
“The goal is for all of us to strengthen our defense capabilities, to do everything so that our border is protecting our societies,” said Latvian Defense Minister Andris Spruds, who commissioned his country’s military to examine whether it would make sense to pull out of the land mine treaty, known as the Ottawa Convention. “We should defend our territory from the first inch.”
Spruds and his Lithuanian and Estonian counterparts recently agreed to build what they call a Baltic Defense Line, a coordinated system of bunkers and fortifications. Until recently, much of the border between Russia and those countries was rolling fields and open pine forest, with little to impede crossings. The countries began constructing fences in 2020 to deter migrants whom Russian authorities were sending over in a bid to destabilize European neighbors. Now, the border is set to become far more militarized, with plans to install sensors and physical obstacles to block tanks and other vehicles — as well as an investment in an arsenal of antitank mines and remote-detonated mines that can be deployed if Russian troops start massing at the border.
The fortification plans are taking lessons from Russia’s defensive lines in occupied eastern Ukraine, where the military dug hundreds of miles of trenches, scattered concertina wire and antitank barriers, and laid unusually extensive mine fields. When Ukrainian forces attempted to clear mines away, Russian drones were able to direct artillery fire toward them, leading to minimal territorial gain for the Ukrainians despite major ambitions.
“Russia has in place of manpower used mine power,” said James Cowan, a former British army general who is the chief executive of the HALO Trust, a mine-clearance organization.
Lithuania and Latvia are each about the size of West Virginia, and Estonia is even smaller, meaning that unlike in the much larger Ukraine, there would be little territory for them to fall back to if Russian tanks rolled across the border.
“We can expect that within the next decade, NATO will face a Soviet-style mass army that, while technologically inferior to the allies, poses a significant threat due to its size, firepower and reserves,” the director general of the Estonian Foreign Intelligence Service, Kaupo Rosin, wrote as part of an annual intelligence assessment released this month.
Finland, which has had a separate domestic conversation about land mines, significantly extended NATO’s border with Russia when it joined the alliance last year. Driven by security concerns along its 832-mile Russian frontier, Finland signed up for the anti-personnel land mine treaty more than a decade after most countries, and it finished destroying its stockpiles only in 2015. Many policymakers have questioned the decision in the past, including president-elect Alexander Stubb, although the country has no current plans to pull out of the convention.
Some Baltic policymakers say that despite NATO defense guarantees, Ukraine’s recent experience heightens the imperative to hold back a Russian invasion. In 2022, world leaders initially presumed Kyiv was lost, and it took about 10 days for attitudes — and assistance — to switch to a mode that would help Ukrainians reclaim territory rather than escape.
But no country plans to withdraw from the anti-personnel land mine treaty for now. In Latvia, Spruds said the benefits are outweighed by the drawbacks, including the risk to civilians and the international blowback that might come from such a move.
“There is a spectrum of land mines we can use. And Latvia is absolutely willing to develop this capability,” he said. “We have in our arsenal land mines, and we will be developing capability without obtaining those land mines which are prohibited by convention.”
The treaty allows countries to use antitank mines, which are considered safer for civilians because they require far more downward pressure to detonate than that caused by a human walking over them. The treaty also allows for the use of smaller, remote-controlled mines that could kill individual soldiers, so long as they are capable of being operated by someone who can distinguish between military and civilian targets. Those types of mines are far more expensive than old-fashioned anti-personnel mines, which as part of conventional military doctrine are scattered around an antitank mine to make the larger charge harder to disable.
Neither the United States nor Russia is a party to the anti-personnel mine treaty, which has been signed by 133 nations, although the Biden administration has announced that it plans to adhere to its rules except in South Korea, where it uses the devices as tools against a North Korean invasion.
The Biden administration has not sent banned anti-personnel mines to Ukraine, but the Pentagon has said it has sent an unspecified number of Cold War-era antitank mines to aid Kyiv in its fight.
Anti-personnel mines are “difficult to manage,” said Kusti Salm, the permanent secretary of the Estonian Defense Ministry. “Eventually it’s going to be demined not by your opponent or the enemy, but it will be demined by our own children and animals.”
Estonia plans to build 600 small, fortified bunkers along its border with Russia, with Latvia and Lithuania expected to build even more since their land borders are longer. Each bunker will be able to hold about 10 soldiers and withstand an artillery hit, planners said.
With a fortified border, Russia would require “much more resources, much more firepower” for an attack, Salm said. The Kremlin’s need to accumulate these additional forces, he noted, would give NATO nations earlier warning of an imminent attack, giving them more time to prepare.
“Our plan is to massively use antitank mines and sight mines and all sorts of other mines,” Salm said. “It has been our policy since very early on. We supplied Ukraine with tens of thousands of antitank mines. We are replenishing these stocks.”
Some anti-mine campaigners say that even mines permitted under the treaty can pose a problem to civilians. They warn that any type of unmonitored mine can be a safety risk.
When the treaty was being negotiated, many international anti-mine groups wanted antitank mines to be banned, “because a lot of refugee transfer buses and vehicles were getting blown up,” said Ken Rutherford, a political science professor at James Madison University who survived a land mine blast in Somalia in 1993.
“Just because antitank mines are not included in the Ottawa treaty doesn’t make them humanitarian or sensible,” he said.
But some policymakers say front-line countries should go further, withdrawing from the treaty and doing everything they can to make the Kremlin think twice about crossing the border.
“In Ukraine, we see that all those fortified lines are actually very effective,” said Janis Garisons, who until last month was the top civil servant in the Latvian Defense Ministry. “It’s good deterrence if Russians know that we are ready to use everything at our disposal.”
For now, leaders appear likely to focus on what they are allowed to do under their current treaty commitments — but to continue to watch the fighting in Ukraine for new lessons.
“The battlefield in Ukraine is an important example of how modern warfare takes place, which actually combines both the newest technologies and old, cheap solutions,” said Spruds, the Latvian defense minister. “We see the mixture of everything: 19th-century ambition, 20th-century trench warfare brutality and 21st-century technologies. Many things previously taken for granted should be corrected.”