CLIMATEWIRE | The Defense Department has a new search-and-destroy mission. It’s on the hunt for climate-related programs and studies.
Last week, the Pentagon announced it had canceled multiple studies related to climate — including several that sought to determine whether a hotter planet could lead to more instability in Africa. In addition, the Defense Department has spent the last few weeks combing outside contracts for the term “climate” with the intent to zero out all related work, according to two former Pentagon officials.
The purge is being driven broadly by President Donald Trump, who previously has described climate change as a hoax. But it has taken on extra urgency under the leadership of Defense Secretary Pete Hegseth, who has long rejected climate science and has vowed to eliminate all the Pentagon’s climate-related work.
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“The @DeptofDefense does not do climate change crap,” Hegseth wrote on X on Sunday. “We do training and warfighting.”
It’s unclear how many climate initiatives are at risk for cancellation and how much money their erasure would save.
The Pentagon said canceling 91 studies on climate and other topics would save $30 million, but it did not disclose how much money the Defense Department could save by eliminating other climate-related programs and studies. Pentagon officials did not respond to questions from POLITICO’s E&E News seeking answers on these topics. Instead , they issued a statement that said the Defense Department was working to “restore the warrior ethos and refocus our military on its core mission of deterring, fighting and winning wars.”
“Climate zealotry and other woke chimeras of the Left are not part of that core mission,” Pentagon spokesperson John Ullyot said in a statement.
But defense experts warn the rush to cancel these programs could backfire on the Pentagon. Studying and preparing for global warming isn’t a liberal luxury, they say — it’s essential to better understand how climate change could influence both global politics and battlefield conditions.
It’s about “missions and not emissions,” said John Conger, who served as principal deputy undersecretary of Defense in the Obama administration.
As an example, he pointed to the risk that rising sea levels and more extreme storms pose to the constellation of U.S. military installations worldwide.
“Climate affects the military mission, it affects your ability to do your job,” said Conger, who is a senior adviser to the Council on Strategic Risks.
“In particular with infrastructure, where you want to be able to endure extreme weather or other weather effects in order to retain capability,” he said. “But also in the battlefield, you want to be able to deal with the ambient conditions and the environmental conditions in order to conduct your warfighting mission.”
The Pentagon’s broad approach to global warming was outlined in a climate adaptation plan the agency released last year. It found that climate change was costing taxpayers billions of dollars, threatening supply chains and disrupting military readiness. Those impacts have affected training, infrastructure and the Defense Department’s “ability to execute its mission,” the report said.
“To train, fight, and win in an increasingly complex threat environment, we must consider the effects of extreme weather and climate change at every level of the enterprise,” the report found.
For years, the military’s strategy has been to incorporate clean energy and alternate fuel technology into operations — largely for strategic reasons, rather than cutting greenhouse emissions.
But Trump and Hegseth both have targeted that work as wasteful and unnecessary. In particular, the two men have taken aim at efforts to develop hybrid tanks; on the campaign trail, Trump falsely claimed their purpose was to appease environmental groups.
In reality, hybrid tanks largely run on diesel and are designed to have increased range by being less reliant on fuel. They also provide an operational advantage because they can switch to a hybrid battery to cut a heat signature that could be more easily detected on enemy radar.
The army is now developing a hybrid-electric tank, which is essentially a modernization of the Bradley Fighting Vehicle, though they are not yet deployed. The Defense Department has been exploring the development and deployment of additional hybrid tactical vehicles by 2035. A 2022 climate strategy plan also called for the development of all-electric tactical vehicles that could be used by 2050.
That plan has now been deleted from the Defense Department’s website.
There are “tremendous operational and capability advantages” to using clean technology in the military, said Richard Kidd, who served as deputy assistant secretary of defense for environment and energy resilience in the Obama administration.
He said clean energy technology is absolutely a part of modern warfare because today’s battle spaces require “electricity to charge drones, power AI at the edge, support directed energy weapons and certain types of hybrid-electric tactical vehicles.”
“If the administration throws out everything that has the word ‘climate’ in it — the people, the structures and the contracts — it risks undermining its own goals about energy dominance, competition with China, and accelerating the deployment of nuclear power,” he said.
That said, there remains some lingering frustration with the Biden administration over its efforts to infuse climate planning into a broad swath of military programs, including some that never were designed for emissions cutting.
The push may have unnecessarily put a target on those programs, said Bret Strogen, who served as the energy and sustainability adviser for the assistant secretary of the Army in the first Trump administration.
“Climate resilience, climate adaptation, preparing for floods, drought, that is — that is an area that DOD and everyone else needs to pay attention to,” he said. “Climate mitigation and reducing emissions is not the DOD’s role.”
One defense expert warned the effort to eliminate climate programs and studies could create a future blind spot for the Pentagon.
It could leave the military unprepared for the role of climate change as a threat multiplier, where more extreme storms, heat conditions and regional conflicts could hamper and harm U.S. troops and their warfighting abilities, said Sherri Goodman, deputy undersecretary of Defense for environmental security in the Clinton administration.
She said U.S. allies — and rivals — will be fully utilizing that scientific intelligence.
“If we put our heads in the sand, that’s a gift to China,” said Goodman, author of “Threat Multiplier: Climate, Military Leadership, and the Fight for Global Security.”
“They’re aware of the climate risks they are faced with in their own country and around the world,” she added. “And they are just looking to fill the power vacuum that we’re creating.”
Reprinted from E&E News with permission from POLITICO, LLC. Copyright 2025. E&E News provides essential news for energy and environment professionals.
