Ukraine war: Can bogs help protect Europe against Russian invasion?

Finland and Poland are reviving a Cold War-era tactic with a green twist, restoring peat bogs along their Russian borders and turning swampland into both a natural defence line and a carbon sink.

In February 2022, as Russian tanks rolled toward Kyiv, a desperate Ukrainian move stopped them in their tracks: the deliberate flooding of the Irpin River basin. The swampy terrain turned into an impassable quagmire for Moscow’s armour, a manoeuvre that bought Kyiv crucial time and sent images of stranded Russian vehicles around the world.

Three years later, that battlefield lesson is shaping defence thinking on NATO’s eastern flank. Finland and Poland are now considering the revival of long-drained peat bogs along their borders with Russia, not only as natural obstacles to slow an invasion but also as a tool in the fight against climate change, Politico reported.

Most of these wetlands, once widespread across northern and eastern Europe, were drained over the last century to create farmland. The dry peatlands became easier for vehicles to cross but at a cost: they release massive amounts of stored carbon dioxide into the atmosphere, fuelling global warming. Restoring them could flip that equation, locking away carbon while complicating the movement of tanks and armoured personnel carriers.

Poland’s defence ministry has already woven the idea into its €2.3 billion “Eastern Shield” border fortification project, which includes measures for peatland formation and reforestation along frontier zones.

“It’s a win-win situation that achieves many targets at the same time,” Tarja Haaranen, director general for nature at Finland’s environment ministry was quoted by Politico as saying, confirming that Helsinki will open talks on a pilot project this autumn.

The strategic logic is not new. Marshes have historically served as natural fortifications — from Germanic tribes ambushing Roman legions in boggy terrain in A.D. 9, to Finnish wetlands stalling Soviet forces in the 1940s. But reviving bogs deliberately for both ecological and military purposes would be a first.

The potential is significant. Peatlands cover just 3 percent of the planet yet store a third of its carbon, twice as much as forests. When drained, however, they become sources of emissions; across the EU, half of all peatlands are degraded, releasing 124 million tons of greenhouse gases annually, nearly equivalent to the entire output of the Netherlands.

By restoring these landscapes, Finland and Poland could simultaneously meet EU climate commitments under the bloc’s new Nature Restoration Law which requires countries to rehabilitate 30 percent of degraded peatlands by 2030 while bolstering their defensive depth against Russia.

Security analysts argue that in a potential conflict, rewetting boggy zones would force invading troops into predictable, narrow corridors, easier to defend with conventional weapons. The tragic deaths of four US soldiers in Lithuania earlier this year, after their 63-ton armoured vehicle sank into a bog, underline the hazards that wetland terrain poses even to advanced militaries.

Still, challenges remain. Farmers, who have long relied on drained peatlands for cultivation, are wary of restoration projects that could reduce arable land. Governments in the Baltics have shown limited enthusiasm so far, despite peatlands covering nearly 10 percent of their territory. And ecologists caution that wartime flooding, as seen in Ukraine, can devastate local communities and wildlife if done hastily.

But supporters argue that with careful planning, Europe can use its wetlands as both shield and carbon sink. “Perhaps it’s better to think ahead instead of being forced to act in a hurry,” said Estonian restoration ecologist Aveliina Helm. “Ukraine didn’t have that choice. We do.”