Climate change poses broad national security risks including to military infrastructure and bases, which are increasingly threatened by rising sea levels, floods and hurricanes, to global supply chains, and to health. 11,000 cases of heat exhaustion and heat stroke have been diagnosed in the U.S. military since 2018 and according to one study, half of all coastal bases will experience 270 or more flood events per year by 2050. The military is also increasingly at the frontline of the climate crisis, responding to 230 climate-related emergencies globally since 2022. At the same time, the U.S. military has a massive environmental impact as the largest institutional consumer of hydro-carbons in the world, with militaries globally producing an estimated 5.5% of emissions (estimated because military emissions reporting is not required), with adverse effects on air quality, biodiversity, and the health of local populations.
Climate change is what the U.S. military has called a “threat multiplier.” posing a direct threat to political stability and can either exacerbate or trigger violent conflicts.
The Government Accountability Office (GAO) has highlighted the pressing nature of climate-related threats. Their 2022 report outlines how rising sea levels, increased frequency of extreme weather events, and other climate impacts pose direct risks to military and civilian infrastructure, potentially affecting migration patterns and global stability.
In 2024, the U.S. Department of Defense (DoD) released its Climate Adaptation Plan for 2024–2027, building upon previous strategies to enhance resilience against climate-induced challenges. This plan emphasizes the integration of climate considerations into all aspects of military operations, infrastructure, and supply chains to maintain operational readiness in the face of evolving environmental conditions. The DoD's 2024–2027 Climate Adaptation Plan outlines five key lines of effort:
Climate-Informed Decision-Making: Incorporating climate considerations into strategic, operational, and tactical decisions.
Training and Equipping the Force: Ensuring military personnel are prepared to operate under extreme weather conditions and other climate-related challenges.
Resilient Infrastructure: Upgrading and maintaining infrastructure to withstand climate impacts, thereby ensuring the longevity and effectiveness of military installations.
Supply Chain Resilience and Innovation: Enhancing the robustness of supply chains to prevent disruptions caused by climate-related events.
Collaboration: Working with federal agencies, international allies, and other stakeholders to bolster collective climate resilience efforts.
These initiatives reflect a comprehensive approach to mitigating climate risks and ensuring that the U.S. military remains agile and effective in a changing environment.
Internationally, climate change is increasingly viewed as a catalyst for conflict, exacerbating resource scarcity, displacement, and social tensions. A 2023 analysis by the RAND Corporation emphasizes that the military cannot afford to overlook the destabilizing effects of climate change, particularly in fragile regions.
Furthermore, the Center for Climate & Security has documented various defense-related climate initiatives, including the U.S. Army's Climate Strategy Implementation Plan for 2023-2027, which aims to reduce greenhouse gas emissions and enhance operational resilience.
In January 2025, President Donald Trump initiated significant shifts in U.S. climate and energy policies.
He declared a national energy emergency to increase energy security, primarily to boost fossil fuel development.
He rescinded Biden’s 2021 Executive Order which outlined climate change as a national security concern.
He withdrew from the Paris Agreement again, removing the United States from the climate fight internationally.
The new administration prompted the Department of Defense (which Trump has moved to rename the Department of War) to reassess its climate security strategies.
In line with Trump’s strategy of “denial by erasure,” an overhaul of federal agency websites, including the EPA, NASA, USDA, and the Department of Defense, has removed all mentions of climate change and wiped climate data from public access. The Department of Defense Climate Resilience Portal was taken down in February 2026. Climate Action Plans for the Army, Navy, Air Force, and Coast Guard have disappeared from their websites. (There are groups tracking this disappearing climate data and archiving it for the public).
The 2026 budget request for the Pentagon moved to cut $1.6 billion in “wasteful” climate spending, including a $6 million grant for decarbonizing Navy ships, and, for the first time in over a decade, the Annual Threat Assessment presented to Congress made zero mention of climate change.
On March 7, 2025 the DoD announced it was “scrapping its social science research portfolio” to save $30 million, cutting 91 studies including studies on climate hazards in Africa, food stability, and ocean ecosystems.
In June 2025, the DoD announced it would halt data collection by the Defense Meteorological Satellite Program, which provides satellite data to scientists and weather forecasters on ocean conditions and weather information, crucial for tracking hurricanes and storms. The DoD later reversed this decision, and will continue sharing the data until the program ends in September 2026.
In December 2025, the Trump administration paused five offshore wind projects citing unspecified national security risks. The Trump administration had previously claimed offshore wind is a risk due to “clutter,” or radar interference from turbine blades and reflective towers. All that, despite the fact that the projects had already undergone years of review by state and federal agencies including the Coast Guard and the Air Force, and the Department of Defense approved each step of the permitting process. It was no surprise that in January 2026 four of those pauses were reversed:, a federal judge ruled that the Danish company Orsted can proceed with the construction of its wind farm, Revolution Wind, off the coast of Rhode Island, another ruled that Equinor can proceed with Empire Wind in New York, another in Boston granted a preliminary injunction allowing Vineyard Wind to resume construction, and another Coastal Virginia Offshore Wind, the largest offshore wind project in the U.S. was also permitted to move forward, under the developer Dominion Energy.
The 2025 National Security Strategy of the U.S. states “we reject the disastrous ‘climate change’ and ‘Net Zero’ ideologies that have so greatly harmed Europe, threaten the United States, and subsidize our adversaries.”
Secretary of Defense Pete Hegseth vowed to eliminate all climate-related initiatives, tweeting “The @DeptofDefense does not do climate change crap. We do training and warfighting.” And Pentagon spokesperson John Ullyot said “Climate zealotry and other woke chimeras of the Left are not part of [the Pentagon’s] core mission.” Echoing this logic, according to a Whitehouse spokesperson, the U.S. did not participate in COP30 because “President Trump will not jeopardize our country’s economic and national security to pursue vague climate goals that are killing other countries.”
This rhetoric represents a huge reversal of previous national security and climate security principles. According to Tom Ellison of the Center for Climate and Security, the “recognition of climate change as a national security issue has traditionally been kind of a rare spot, an area of bipartisan treatment of climate change.” Embedded in the Trump administration’s arguments is a reversal from climate change as a national security risk to climate change ideology as a national security risk. Climate change becomes a “chimera,” a false threat that will disappear if you do not look at or talk about it. Therefore, everything that acknowledges the existence of climate change must be eliminated - websites scrubbed, data disappeared, mitigation and adaptation efforts and renewable energy declared security risks. Trump can then declare emergencies and cite national security as an excuse to accelerate the development of AI data centers, dismantle clean energy projects, and shut down offshore wind.
On January 7, 2026, Trump withdrew the U.S. from 66 international organizations that “no longer serve American interests” including the UNFCCC and the IPCC. The Trump administration framed the withdrawal as a national security issue, claiming their “radical climate politics” undermine “U.S. sovereignty” and withdrawing will allow the prioritization of “infrastructure, military readiness and border security.”
