Restoring forests, wetlands and peatlands could help defend national borders as well as tackle climate change, according to new research from the University of East London (UEL).
The study introduces the concept of “defensive rewilding” - the intentional, pre- or mid-conflict restoration of ecosystems to shape terrain in ways that can slow, redirect or impede military advances, while delivering environmental benefits.
The research responds to what the authors describe as a growing “guns versus climate” dilemma, where investment in military capability can come at the expense of action on climate change and biodiversity loss. It reframes the environment as a potential “force multiplier” in national defence.
Rather than treating environmental policy and defence as competing priorities, the research suggests the two can be closely aligned. Unlike temporary battlefield measures such as minefields or field fortifications, defensive rewilding operates at a strategic scale, shaping terrain across entire regions before conflict begins.
Examples include restoring wetlands to create waterlogged ground that is difficult for armoured vehicles to traverse, planting forests to restrict visibility and movement, and re-naturalising rivers to complicate crossing operations. Alongside these defensive effects, such interventions also support carbon storage, flood mitigation and biodiversity recovery.
The authors argue this approach can act as a form of “deterrence by denial”, making attacks more difficult or costly and therefore less likely.
The research draws on both historical and contemporary examples to show how terrain shapes conflict, from the deliberate flooding of landscapes during the First World War to more recent examples from Ukraine, where rivers and saturated floodplains have slowed and redirected armoured advances.
Sam Jelliman, researcher at UEL’s Sustainability Research Institute (SRI) and co-author of the study, said, “Rather than seeing defence and climate action as competing priorities, our research shows they can reinforce one another. You can invest in landscapes that are both more resilient environmentally and more secure militarily.”
Peatlands are a particularly strong example. Their low ground-bearing capacity makes them difficult for even light armoured vehicles to cross, while also acting as some of the most effective long-term carbon stores.
“Peatlands are probably the most challenging terrain to cross, and they’re also one of the most effective natural carbon stores. That makes them a particularly powerful focus - they deliver both defensive and climate benefits at the same time,” Jelliman added.
While the concept offers long-term advantages, the researchers note it would need to be carefully balanced against land use, governance and environmental considerations, and implemented as part of a broader defence strategy.
Research Impact Leader at UEL Alan Chandler , who co-authored the study, said, “Nature-based solutions like this challenge us to rethink what infrastructure really means. By working with natural systems rather than against them, we can build resilience that is both sustainable and strategic. It also shows how integrating ecosystem restoration into national security planning could offer a cost-effective and forward-looking approach to defence in an era of growing geopolitical and climate pressures.”
The study also highlights that restored ecosystems can be more cost-effective and longer-lasting than conventional defensive infrastructure, while delivering additional environmental benefits.
The study, Defensive Rewilding: A Nature-Based Solution for National Security , by Sam Jelliman, Brian Schmidt and Alan Chandler, was published in The RUSI Journal.
The RUSI Journal
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Defensive Rewilding: A Nature-Based Solution for National Security
7-Apr-2026