
The big focus for Defence and Australian strategic policy is AUKUS and China. Australia and our northern bases are willingly being integrated into the United States’ policy of strategic confrontation with China, and perhaps a future war. Only 16 per cent of Australians currently support military participation in such a conflict. The AUKUS submarines, if they ever materialise, are essentially offensive in nature.
The Defence Strategic Review (DSR) rubber-stamped this view. It exhibited the unwillingness of the government to look at a broader range of strategic risks. If it had, it would have considered the big picture issue such as the warnings by catastrophic risk analysts that AI, digital disinformation and a growing range of autonomous systems may already be undermining democratic principles, fanning social division and enhancing the power of an autarchic oligarchy with significant security consequences.
Together with senior former security leaders, I submitted to the DSR that global inaction has resulted in climate change “becoming an immediate existential threat to humanity”, and together with nuclear war is “the greatest threat challenging Australia’s security”. We said it should be the primary focus of the DSR, requiring “a fundamental reframing of Australia’s defence and security strategy”, away from just the traditional nation state geopolitics, to focus on unprecedented global co-operation rather than conflict, particularly with China.
But the Review was narrowly focussed and did not ask the big questions about human security: what are the greatest threats to Australians’ future livelihood, health, economic well-being and safety?
In the international reviews and surveys of the greatest threats to the human future, such as those undertaken annually by the World Economic Forum, one threat is consistently identified above all others: climate disruption. The Forum’s 2023 survey of global leaders found that the biggest three risks in the coming decade were all climate-related, whilst “geo-economic confrontation” (read China) came in ninth. The US Defence Secretary has called the climate risk “existential”, as has the UN Secretary-General, and even Australia’s climate minister.
So where does that figure in our defence and security strategy? It currently doesn’t, and the major piece of work that would help inform the parliament and start a public debate on that issue — the 2022 Office of National Intelligence climate and security risk assessment — remains locked in a bottom drawer, never to be spoken about.


Australian Deputy Prime Minister and Australia Defence Minister, Richard Marles, and Australian Foreign Minister Penny Wong, speak on board HMAS Canberra in Sydney, Australia, November 12, 2025. REUTERS/Hollie Adams
Australian Deputy Prime Minister and Australia Defence Minister, Richard Marles, and Australian Foreign Minister Penny Wong, speak on board HMAS Canberra in Sydney, Australia, November 12, 2025. REUTERS/Hollie Adams
The Defence Review was narrowly focused and did not ask the big questions about human security: what are the greatest threats to Australians’ future livelihood, health, economic well-being and safety?
Asia is a disaster alley for climate disruption. With another failure of the international climate-policy making process, this year in the petrostate of Azerbaijan, the scientific evidence is clear that annual emissions are still rising and we are heading towards 3 degrees Celsius of warming, perhaps in as little as four decades. We need to think and plan now what that means for Defence, given the long lead times.
Already one of the biggest calls of Defence personnel is in response to increasingly extreme fires and floods in Australia, and cyclones in the region. A viable alternative to relieve pressure on Defence has not yet been elaborated. And the government is pouring money into defence infrastructure in northern Australia, seemingly turning a blind eye to the scientific evidence that large parts of our northern region will become unliveable within three decades or so. Bases and essential infrastructure are at risk of becoming non-viable or obsolete.
A new report, “Collision Course: 3-degrees of warming and humanity’s future” from the Breakthrough National Centre for Climate Restoration, provides a graphic picture of where the security challenge in our region is heading. In a 3°C hotter world, new heatwaves, flooding and drought extremes will be beyond our past human experience. Sea-level rise will be in the process of inundating many cities and deltas. Large parts of the tropics will experience “near-unlivable” heat conditions, including across much of South and Southeast Asia.
These events will have unimaginable impacts on food and water security and social stability. States will fail, and nations will become non-viable. There is an unacceptable risk that regional economic and political networks will crash. Both the UN and researchers suggest that at 3 degrees of warming a billion people could be displaced, and looking for better places to live.
What would all this mean for Australia and for Defence? We simply have not started to have that public discussion within the Australian community. This frightening but realistic scenario was discussed at a recent National Climate Security Summit in Canberra. The findings are gloomy.
A credible action plan would include an emergency mobilisation effort akin to wartime-level responses, with accelerated decarbonisation and coordinated actions across all levels of government. It would include the creation of a Climate Threat Intelligence Unit to provide real-time insights into the evolving risks to enable preventive action before crises escalate.
And a leadership role for Australia in the Asia-Pacific, working closely with regional neighbours to strengthen resilience; and strong enhanced regional cooperation on the drivers of forced displacement to ameliorate the potential impacts on regional stability and enhance the capacity of nations to respond.
The failure to take such basic steps would simply be yet another form of climate denial, of not wanting to understand the future that Australia and its Defence Force face. In the wake of another disappointing COP conference, is it now time for us to find another way to hold political leaders to account when they fail to prepare for our future?