1. Opening — two figures that rarely appear side by side
Let me start with two figures.
The first: 2,887 billion dollars. That is the world's total military spending in 2025, according to SIPRI — the Stockholm International Peace Research Institute. It is an increase of 2.9 per cent in real terms, the eleventh consecutive year of growth, and the highest level SIPRI has ever recorded. The global military burden — military spending as a share of world GDP — reached 2.5 per cent, the highest since 2009. The three largest spenders, the United States, China and Russia, together accounted for 1,480 billion dollars, or 51 per cent of the total. NATO's 32 members accounted for 1,581 billion, 55 per cent of world military spending.
The second figure: 5.5 per cent. That is the most widely cited estimate of the share of global greenhouse gas emissions attributable to the world's militaries — and that figure excludes warfare itself. The estimate comes from a submission to the UNFCCC's Global Stocktake and has since been repeated by the Conflict and Environment Observatory (CEOBS), Scientists for Global Responsibility and UNEP. The uncertainty is considerable: Scientists for Global Responsibility gives a confidence interval of 3.3 to 7 per cent.
Put the two figures together and you get the picture of a sector that is enormous, growing — and largely absent from the climate accounts.
That is the premise of the documentary Earth's Greatest Enemy by Abby Martin, available via earthsgreatestenemy.com. The film's own description calls it 'a groundbreaking anti-imperialist environmental documentary' and frames its central claim like this: the Pentagon is 'exempt from international climate agreements', rarely scrutinised in mainstream media, and 'the world's largest single institutional polluter — emitting carbon, contaminating water and scarring landscapes across the globe'. According to the film's website, it is Abby Martin's second feature film; it combines investigative journalism with accounts from affected communities, is produced by The Empire Files, can be streamed and is available on DVD and Blu-ray with 20 minutes of bonus material, and the filmmakers have been on a sold-out global tour. The website asks for donations to fund a nationwide tour with a stated purpose: that the film should be 'a tool for education and organising' and build 'the necessary bridge between the fight to save the planet and anti-militarism'.
The underlying point is clear — that the military sphere is massive, growing and unregulated — and it can be verified. Let me show you how.
2. The exemption: the legal blind spot
You cannot talk about the war machine and ecology without talking about law, because that is where it begins.
When the Kyoto Protocol was adopted in 1997, military emissions were in practice exempted from the reporting obligations under the UNFCCC. Under the 2015 Paris Agreement the exemption was technically removed — but countries were at the same time not required to report them. Reporting was made voluntary. In practice that means it is up to each government whether its armed forces report or reduce anything at all.
The result is predictable. CEOBS — the Conflict and Environment Observatory — runs an ongoing project grading the quality of military emissions reporting to the UNFCCC, and the conclusion is unambiguous: reporting is 'patchy', standards are low, and many countries do not report separate military data at all. Russia, the world's third-largest military spender, for example reports stationary emissions while mobile ones are listed as 'not occurring', 'included elsewhere' or 'not available'.
An analysis of EU countries' military reporting has, according to the magazine CWR, found a gap of around 82 per cent between the reported and the estimated footprint.
The sentence worth remembering: We cannot manage what we do not measure. And we do not measure what we do not want to see.
3. The scale: what we actually know about military emissions
So what is behind the 5.5 per cent?
•First: it is an estimate, not an accounting. That is the whole point. Because reporting is voluntary, there is no consolidated data set, and the estimate is constructed from consumption data, budgets and assumptions about supply chains.
•Second: it does not include warfare. The submission to the UNFCCC's Global Stocktake states explicitly that the 5.5 per cent covers the footprint of militaries and the military technology industry, but not conflict-related sources — that is, infrastructure, landscape fires, the destruction of carbon stocks and reconstruction.
•Third: it is comparable to major civilian sectors. Several sources state that the world's militaries emit roughly the same as civil aviation and shipping combined. And the Climate Change Performance Index puts it sharply: if the world's militaries were a country, they would be the world's fourth largest emitter.
•Fourth: it correlates with the budgets. Military emissions follow military budgets, and budgets are rising. SIPRI notes that world military spending has risen 41 per cent over the past decade (2016–2025). US spending did fall in 2025, but SIPRI itself assesses that the decline is 'likely to be short-lived': the US Congress has appropriated over 1 trillion dollars for 2026, and SIPRI points out that the figure could rise to 1.5 trillion in 2027 if President Trump's latest budget proposal is adopted.
This is not about ill intent in the cockpit. It is arithmetic: jet fuel, armoured vehicles, cargo flights, aircraft carriers, generators on thousands of bases. An empire has to burn to keep running.
4. The toxic trail: PFAS — here the documentation is strong
Emissions are one half. The other is the chemistry — and on this point the sources are unusually solid, because the US military is itself obliged to account for it.
For decades the military has used firefighting foam containing PFAS — the so-called 'forever chemicals' — to extinguish fuel fires on bases and in aircraft hangars. The substances practically do not break down, and they have contaminated groundwater and drinking water.
The scale, from two independent accounts:
The Environmental Working Group (EWG) has, through Freedom of Information Act requests, defence reports and public databases, mapped 721 military sites in the United States with known or suspected PFAS discharges — in all 50 states and three territories. At 630 of the sites, water samples and laboratory tests have confirmed contamination of drinking water or groundwater. At the remaining 91 there is suspicion, and further testing may uncover more. The background is that military rules for more than five decades required the use of PFAS-based foam during training exercises.
The US Department of Defense itself states that, as of 30 June 2026, it has assessed that 727 active military installations, BRAC sites, National Guard facilities and former defence properties require investigation for PFAS. Preliminary assessments and site inspections have been completed at 709 of them. At 119, 'no further action required' has been concluded, while 590 have been moved on to the next phase of the cleanup process under CERCLA.
A veterans' legal review states that the military has identified almost 700 bases requiring remediation for PFAS in groundwater, and that the department provided bottled water and installed water treatment systems at these sites at an estimated cost of 3 billion dollars in 2020–2021 alone.
PFAS is linked to several forms of cancer as well as reproductive and immune system damage. Here the war machine and ecocide quite literally go hand in hand: the destruction continues long after the fighting has ended, in the bodies of the people who live next door.
5. The ecological bill of war: Gaza
Then there is the warfare itself — the part the 5.5 per cent figure does not cover.
In September 2025 UNEP published its second environmental assessment of the Gaza Strip, prepared at the request of the State of Palestine. The report covers the period up to 1 September 2025, and UNEP notes that military operations were ongoing at the time of writing.
Based on remote sensing, UNEP found that the following had been damaged as of May 2025:
•97.1 per cent of tree crops
•82.4 per cent of annual crops
•95.1 per cent of shrubland
•89 per cent of grassland and fallow areas
UNEP's conclusion is brief: 'Food production is not possible at scale.' The soil is contaminated by munitions, solid waste and untreated sewage, and the degradation of soil structure through loss of vegetation and compaction from military activity has reduced water infiltration.
At the same time: 78 per cent of Gaza's estimated 250,000 buildings are destroyed or damaged. That has generated 61 million tonnes of rubble — about 20 times the combined amount of debris from all previous conflicts in Gaza since 2008, and by UNEP's reckoning roughly the same as 15 Great Pyramids of Giza or 25 Eiffel Towers by volume. Around 15 per cent of the rubble is assessed to be at relatively high risk of contamination with asbestos, industrial waste or heavy metals if waste streams are not sorted effectively early on. UNEP states that over 500,000 people in Gaza are in famine-like conditions, while around 1 million are in food crisis.
Independent research points in the same direction: geographer He Yin of Kent State University has tracked the vegetation destruction via satellite images and tells Yale Environment 360 that 89 per cent of annual crops and 98 per cent of tree crops have been damaged after two years of war. A peer-reviewed article by Yin from 2025 found that 64–70 per cent of tree crop fields and 58 per cent of greenhouses were already damaged as of 27 September 2024 — after barely a year of war.
The point is not to rank suffering. The point is that the war's climate account is systematically omitted — and that these are precisely the emissions that are hardest to reverse.
6. Ukraine: the first complete calculation for an ongoing war
Ukraine is interesting for another reason: it is where someone for the first time has tried to add up the entire climate effect of an ongoing war.
According to the Climate Change Performance Index, researchers have estimated that the first two years of Russia's invasion emitted more than an industrialised country like the Netherlands emits in a full year. It is the first comprehensive calculation of the climate impact of an ongoing armed conflict.
At the same time, Ukraine illustrates the other side of the equation: according to SIPRI's data for 2025, Ukraine spent around 40 per cent of its GDP on the military — the highest share in the world, far above Russia's 7.5 per cent and Israel's 7.8 per cent. That is what war does to a country's economy: it eats almost everything else.
7. Why it is connected — the structure
Now to the real question: is it a coincidence that the most polluting sector is also the least regulated? No — and the explanation is structural, not moral:
•1. The exemption is self-reinforcing. Because reporting is voluntary, there is no data set. Because there is no data, no one can set binding targets. Because there are no binding targets, nothing changes.
•2. The security argument closes the debate. When something is defined as national security, it is moved out of ordinary environmental regulation and into a space where democratic control is weaker.
•3. The war economy is permanent. Eleven years of uninterrupted growth in military spending and a global military burden of 2.5 per cent of GDP — the highest since 2009. An industry with that growth rate has no incentive to scale down.
•4. Destruction is also a market. Reconstruction, rearmament and replacement of materiel is demand. Gaza has to clear 61 million tonnes of rubble. That is a job someone will be invoiced for.
The film Earth's Greatest Enemy hits exactly this point when, according to its own description, it wants to 'challenge audiences to rethink the hidden costs of a global military empire and its planetary consequences' — and when the filmmakers say the goal is to build a bridge between the fight for the planet and anti-militarism. That is an organisational point, not merely a journalistic one: the two movements have so far talked past each other — until now.
8. It is not just the US
It is easy to make this an American story. It is not.
SIPRI's figures for 2025 show that even as US spending fell, European spending rose by 14 per cent to 864 billion dollars, and Asia and Oceania by 8.1 per cent to 681 billion. Military spending outside the United States rose by 9.2 per cent in total. 23 of NATO's 32 members spent at least 2.0 per cent of GDP on defence by SIPRI's method.
And Denmark is part of that movement. It is worth saying out loud in a Danish context: we happily discuss the climate footprint of agriculture, transport and construction. We almost never discuss the military's. That is not because the military is climate-neutral — it is because there is no figure to discuss.
9. What one can object — and what still stands
A presentation without counterarguments is agitation, not argumentation. Here are the strongest objections:
'The figures are uncertain.'
Correct. 5.5 per cent is an estimate with a confidence interval of 3.3–7 per cent, and it excludes warfare. But the uncertainty is itself the product of missing reporting — it is an argument for better data, not against the problem.
'The military cannot simply be deprioritised when there is war in Europe.'
That is a legitimate trade-off. But there is a difference between maintaining a defence and refusing to measure its footprint. Transparency is not disarmament. One can demand accounting without demanding abolition.
'Some countries do report.'
Yes — some countries publish military emissions data. The problem is that the reporting is voluntary, unsystematic and often not separated from other categories, so the figures cannot be compared across countries.
'Ecocide is a political word, not a legal category.'
It is true that ecocide does not yet have the same status in international law as genocide or war crimes. Political and legal work is under way to change that, and several countries have introduced ecocide provisions in their own legislation. For now, ecocide is a demand, not a verdict. It is worth being precise about when using the word.
What remains after the objections is nonetheless this: a sector that accounts for a significant share of the world's emissions is at the same time the only major sector without binding climate targets. That holds regardless of how one otherwise views defence policy.
10. Conclusion — what then?
Three concrete demands that do not require agreement on security policy:
•1. Binding reporting. Military emissions must be included in national climate accounts and in the NDCs, not be voluntary. That is also the recommendation in the academic literature on the subject.
•2. Cleanup and responsibility. PFAS contamination at military facilities must be mapped and paid for by the polluter — also outside US borders. Here the American accounting is a model, not a letter of exoneration.
•3. A bridge between the movements. The climate movement must be able to say the word 'military'. The peace movement must be able to say the word 'climate'. That is exactly what the filmmakers behind earthsgreatestenemy.com are trying to do with their screening tour.
I will end by returning to the two figures from the beginning: 2,887 billion dollars for destruction. 5.5 per cent of emissions — without the wars being counted.
That is not a paradox. It is a system working as designed. The question is whether we will keep choosing not to measure it.