The Military’s Carbon Blind Spot: Security, Secrecy, and Sustainability

I read a piece over the weekend that got me thinking: when we talk about the energy transition, we rarely mention the military. Solar panels, electric cars, heat pumps—those are the poster children of decarbonisation. But tanks, fighter jets, and sprawling bases? Not so much. And yet, as The Guardian article points out, the world’s militaries account for 5.5% of global emissions—more than aviation, less than steel. That’s a significant share, especially when you consider the scale and permanence of military infrastructure across the globe. (Read the full article here, written by: Ajit Niranjan).

Only two European countries—Austria and Slovenia—have publicly set net zero targets for their armed forces. The rest either haven’t quantified their emissions or simply state they are “contributing” to national climate goals. It’s easy to see this as a blind spot—and in some ways, it is. But we also have to give the military some benefit of the doubt: there are good reasons they can’t lay out all their plans in public.

Defence is not like any other sector. If a country were to announce that it plans to retrofit all its bases, bunkers, and fuel depots over the next five years, it would risk exposing vulnerabilities that could be exploited. Stealth, strength, and resilience are the core priorities—and that means information about infrastructure upgrades, supply chains, or energy use will always be carefully controlled. Even if large-scale decarbonisation efforts were already underway behind the scenes, it’s unlikely we’d ever see those plans in full detail.

That said, I’m convinced most militaries are taking the climate challenge seriously. They know that climate change is a security risk—a destabilising force that can fuel conflict, disrupt resources, and threaten stability. And they understand that, over the long term, a military reliant on fossil fuels is a military exposed to geopolitical and economic risks.

The real question is: How can we foster transparency and progress without compromising operational security?How do we ensure that massive increases in defence spending—like the 17% jump in Europe last year—also drive green innovation and don’t lock us into a future of carbon dependence?

We need a new kind of conversation. Not one that demands the impossible—like public audits of every military facility—but one that pushes for serious, long-term commitments. Climate action is not separate from security; it’s part of it.