In the 2026 National Defence Strategy (NDS), Australia should outline credible objectives to combat climate insecurity. This would help protect Australia’s long-term defence capabilities, support regional balance and prepare for intersecting security risks.
While climate issues may seem tangential to military capability, Australia’s climate inaction threatens to undermine national interests. Under current climate policies, Australia may struggle to improve national resilience, strengthen deterrence and maintain its role as being an Indo-Pacific security partner of choice.
A siloed definition of defence ignores regional pleas to consider climate change as a legitimate security risk. It splinters international partnerships and pushes Australia’s neighbours towards engagement with China. Embedding higher levels of climate action in the NDS not only serves Australia’s wellbeing but positions it as a nation its allies can rely upon.
Previous defence strategies have excluded substantial climate action. Each iteration of the NDS has introduced innovative framing as a response to Australia’s changing strategic circumstances. The 2016 Defence White Paper evaluated military attacks as ‘no more than a remote prospect’. This shifted in the 2020 Defence Strategic Update, in which Australia pledged to ‘respond with military force, when required’.
The 2026 NDS is predicted to consolidate 2024’s strategy of denial while responding to global conflicts to ensure Australia can not only manufacture capabilities, but sustain and adapt them. Some speakers at ASPI’s Defence Conference in June 2025 urged the new NDS to consider national preparedness outside the traditional notion of war. Discussing one of the event’s panels, ASPI analyst Malcom Davis argued that a ‘whole-of-government’ approach should extend to a ‘whole-of-nation spectrum’.
A whole-of-nation spectrum should include the omnipresent defence risk of climate change and its real effects, including weather-induced migration and agricultural insecurity.
Australia also lacks a National Security Strategy, a policy document that would go beyond defence strategy. As the Perth USAsia Centre’s Alana Ford explained in a July Strategist article, such a strategy is not a luxury, but a necessity. Australia should follow its allies, such as Japan and the United States, and develop such a policy. Without acknowledging climate among diverse security risks, our government will struggle to plan for them in its defence strategy.
While government agencies have taken some action on climate defence, they have been limited. The only climate-related direction in the 2024 document was for the ADF bases to achieve ‘climate adaption and energy resilience.’ In October, the Department of Defence released a Net Zero and Future Energy Strategy, which committed to a 43 percent reduction in defence emissions by 2030 and net zero by 2050. However, the government has acknowledged that climate change still poses an ‘unprecedented challenge’ to food insecurity, population displacement and the deterioration of states in the Indo-Pacific.
Admiral Chris Barrie, former chief of the defence force and executive member of the Australian Security Leaders Climate Group, recommends a wartime approach to climate defence.
As a practical example, this approach would include planning for training at defence bases that may become uninhabitable under current climate change predictions. Left unaddressed, this will become a threat to defence capability.
In recent years, the government has committed $14 billion to hardening Australian’s northern bases. At the same time, climate science and policy institute Climate Analytics has warned that in less than 40 years, facilities in Darwin, Katherine and Bradshaw could exceed 35 degrees C for most of the year. Instances of extreme heat have already cancelled some training and operations. Adapting to these changing conditions may require the use protective gear or a reduction of available hours in the day.
Other climate defence strategies include:
—Integrating climate-induced scenarios in defence planning and wargaming;
—Training ADF personnel in climate literacy; and
—Partnering with climate expert organisations such as the CSIRO for data modelling and intelligence.
Australia’s new NDS comes after failed bid to host COP31, scheduled for November. However, Minister for Climate Change and Energy Chris Bowen will assume the role of president of negotiations, giving Australia ‘unprecedented influence in global climate negotiations’. During COP30, Australia became a signatory to the Belem Declaration, a commitment to creating a ‘just, orderly and equitable’ transition away from fossil fuels. Australia’s adoption of greater climate responsibility should extend to its national defence stance and policies.
Ultimately, climate change and its inevitable impact on defence can’t be ignored. A serious consideration of strategies in the 2026 NDS will equip Australia to better pursue a deterrence-based policy. If Canberra waits until it’s too late to take action, it will jeopardise livelihoods, international relationships and national security.