Beyond the human death and destruction of war, militarisation is also ecologically devastating, with catastrophic consequences for climate. Not only does bombing unleash oil spills, heavy metal contamination and leaking of volatile harmful chemicals, but a 2022 study estimated the world’s militaries accounted for more than 5.5 per cent of total global carbon emissions – more than civil aviation and shipping combined.
This is probably an underestimation. With recent wars and militarisation, military emissions are ballooning. But under the Paris Agreement, governments are not required to report military emissions – a result of lobbying from the US (the country with the largest military in the world), which has since withdrawn from the agreement altogether.
However, a recent estimate of the climate damage of four years of the Russia-Ukraine war suggests it has caused additional greenhouse gas emissions similar to the annual emissions of France.
The heavy reliance on fossil fuels is one reason militarisation is devastating for climate. Fossil fuels are not just used to power aeroplanes, ships, tanks and other military vehicles, but also to power the data centres required for the AI tools now used extensively in military operations to track, detain and kill people.
The US military used AI to capture Venezuela’s president and to strike Iran; Israel has relied on sophisticated AI surveillance systems for genocide in Gaza. Ireland is an important hub in the global data centre network; it is unclear to what extent our data centres are powering militarised AI.
Militarisation is also catastrophic for climate because it increases corporate power and profits among companies and industries that invest heavily in climate obstructionism, sabotaging climate action around the world.
Denying climate science and lobbying to delay climate policies has become common practice across many sectors and governments – including here in Ireland. Corporate power means the needs of large multinational corporations are prioritised over community needs, including investments to reduce climate vulnerabilities.
It is not just weapons manufacturers and the defence industry that expand profits and power through militarisation; big-tech and fossil-fuel companies also benefit hugely. These influential industries have been strategically investing for decades to promote climate denialism and climate misinformation.
But war is the ultimate climate distraction. When war erupts, attention shifts to the immediate struggle of responding to the threat and securing safety and survival. During war, concern about climate disruptions and ecological destruction drop down the list of priorities. The US-Israel war on Iran has effectively launched a new era of global climate obstruction.
The common justification for militarisation is that investing in defence will make us safer. But just like widespread gun ownership does not make the US a safer country, increased militarisation will not make the world a safer place.
In Ireland, despite urgent needs to reduce climate vulnerabilities, the Government seems more likely to succumb to growing pressure to militarise than to prioritise community-focused investments (eg flood prevention measures or affordable housing).
The push for increased defence spending comes from US lobbying and is linked to efforts to weaken EU climate rules and increase EU demand for American fossil fuels. Ireland is vulnerable to this pressure due in part to its precarious economic dependence on foreign direct investment from a handful of US companies.
But Ireland is also in a unique position to resist militarisation. As a small country with strong climate policy and deep commitments to neutrality and peacekeeping, what if Ireland instead chose to demonstrate the powerful potential of a demilitarised society?
Although most Irish people want to protect our sovereignty and maintain our global reputation as peacebuilders, the Government is caving in to the pressure to militarise by planning to remove the triple lock mechanism. The triple lock protects Irish neutrality by ensuring that overseas deployment of our Defence Forces can only occur for UN-mandated peacekeeping missions. But the Defence Amendment Bill (2025), the legislation to end the triple lock, fails to recognise how, without a UN mandate, Ireland could be easily manipulated or coerced to become part of military operations that make claims of peace while waging war, killing people and destroying the planet.
With wars raging and climate chaos worsening, the world needs peacekeepers now more than ever. Neutrality has kept Ireland outside military alliances engaged in destructive wars. It has protected our independent foreign policy and our credibility as a voice for peace and international law.
Ireland’s neutrality is important not just to protect ourselves from being dragged into senseless wars. Ireland’s neutrality is essential to keep alive the hope for just climate futures.
Jennie C Stephens is professor of climate justice at Maynooth University and a co-ordinating lead author of Climate Obstruction: A Global Assessment (Oxford University Press, 2024 available open access).