Extremophiles

What’s the purpose of a military in the era of Overshoot?

As climate demands on military forces become operationally significant, will we need to rapidly shift the load to newly weatherised civilian services, or reimagine the purpose of militaries altogether?

Originally Published in The Geopolitical Climate

The 2025 Security Blindspots report showed that threats to national security are no longer (if they ever were) confined to the actions of hostile actors. Yes, active belligerence and outright territorial war are on the rise worldwide. But if COVID taught us anything, it’s that national security can be severely affected by non-hostile actors. How we conceive of security and its delivery in this light, then, must change.

The rise of non-hostile threats (and the increasingly blurry line between them and outright hostility) is not exactly underappreciated but rather poorly conceived. The threat of rogue AI — or, in certain scenarios, a perfectly normal, functional AI proliferation — is widely feared. Zoonotic diseases have jumped up the risk register. Economic exposures to an unstable, debt-ridden world now threaten catastrophic corrections. Yet none of this seems to have had much impact on how we perceive the role of the Defence establishments, whose task is to deliver national security.

For the rise of climate threats to national security, this question is particularly acute. The MiRCH Tracker by the Council on Strategic Risks shows a clear trend of rising military deployments to respond to climate disasters:

With a rising need to deploy military forces to deal with floods, fires, storms and beyond — and the number of these disasters likewise rising precipitously — it’s worth asking: at what point does the need to deploy military forces for climate disasters become a significant proportion of their operational deployments? And what does that mean for the purpose of a military?

As global temperatures rise — both geopolitically and climatically — there will be a trade-off in how best to use military forces. For nations with large territorial militaries — such as the US National Guard — these questions can be somewhat deferred. But for nations that have only one offensive and defensive force, how best to deploy it will be up for debate. Should it be home protecting lives and livelihoods? Or out fighting in conflict flashpoints?

With withering civil services and a distinctive rise in military expenditure, military forces will, in many cases, become the only branch of the state capable of responding to climate disasters.

In the mid- to long-term, the roles of disaster response and military conflict may even begin to blur. Climate change is a well-known accelerant of civil and interstate conflict — as Erin Sikorsy put it at an event during LCAW: “Climate exploits existing security weak points”. Military forces may find themselves fighting in the same zones where they are tasked with delivering relief.

This, in turn, raises a whole host of new cascading risks. Fighting amid climate disasters and extreme conditions is not only operationally fraught but also likely to increase civilian casualties. In fragile contexts where state trust is low and its control over its armed forces is weak, disaster relief may seem like a punitive expedition. If militaries take over the role of aid agencies, then the competition with combat priorities is likely to degrade both. And in the context of civil conflicts, paramilitaries who can deliver relief the military cannot will seem increasingly viable alternatives to a distant, securitised state.

So, what is the purpose of a military in the era of climate overshoot and proliferating, non-hostile threats? The demands on them are likely to rise, just as the demands of a fractured multipolar system do likewise. Are they well suited to be the answer to these new, extreme conditions? Or do they risk worsening the conflict and disasters they are tasked to resolve?

-Ben Shread-Hewitt