U.S. National Security Heads Turn Away from Climate Research as Threats Mount

Climate change poses major risks to national security. But the Trump administration is scaling back on military programs to assess new threats.

Climate change brings both direct and abstract threats to national security—from fueling deadly extreme weather events to making submarine detection more challenging through warming water. Over the past decade, the U.S. Office of the Director of National Intelligence has formally recognized human-driven warming as a top security risk in its annual threat assessment report, alongside the likes of terrorism and cyberattacks. 

This year, climate change was not mentioned a single time in the report, which was issued at the end of March by the U.S. Intelligence Community.

Experts say this omission is part of the Trump administration’s push to scale back attention and resources on climate change in national security policies. In March, the Pentagon canceled multiple studies related to global warming, while the Defense Department scrubbed climate-related contracts from its portfolio. Defense Secretary Pete Hegseth made his stance clear on the subject: “The @DeptofDefense does not do climate change crap,” Hegseth wrote on X in March. “We do training and warfighting.”

However, a growing body of research shows that training and warfighting could buckle as climate change acts as a “threat multiplier.” 

The Climate Enemy: Military generals have long known that weather can win or lose wars, including some of the battles that established America itself. It was only a few decades ago that the U.S. identified long-term climate change as a formidable foe. 

Some experts argue that the country’s defense officials started considering warming as a threat during the Cold War in the early 1950s, when the U.S. established bases in the melting Arctic to guard against a potential invasion by the Soviet Union. But the conversation really picked up in 1991, when former President George H.W. Bush formally acknowledged climate change as a security issue. More than a decade later, the Pentagon commissioned a report with the name “An Abrupt Climate Change Scenario and Its Implications for United States National Security,” which outlined how this crisis could destabilize the geopolitical environment around the world. 

Since then, the government and universities have poured funding into studying the myriad ways that climate change can drive global conflict. For example, increasingly severe tropical cyclones can force evacuations at crucial military outposts and pull forces for disaster response, which is what happened when Hurricane Milton slammed Florida last October. After these storms, U.S. adversaries such as Russia and China often deploy social media disinformation campaigns to sow political discord in vulnerable regions, David Klepper reports for The Associated Press. 

Droughts and sea-level rise are also exacerbating resource scarcity around the world, which is fueling conflicts in low-income countries such as Guatemala and Honduras. These don’t just pose problems abroad, experts say. 

“It can also impact large-scale migrations, which can destabilize regions and strain national security, leading to humanitarian crises and increased pressure on receiving countries’ resources and infrastructure,” Jason Bordoff, the founding director of the Center on Global Energy Policy at Columbia University, told me last July. I talked to Bordoff about a NATO report that came out last year, which outlined some of the climate-associated security risks to the global community if you want to learn more. 

Overexploitation of natural resources and biodiversity is compounding the problem, according to Emmett Duffy, chief scientist at the Smithsonian Institution’s Marine Global Earth Observatory. He pointed to a conflict in the 1950s between British and Icelandic fisheries over Icelandic cod, known as the “Cod Wars.” The fish’s populations had declined due to overfishing, so the Icelandic government tried to ban British trawlers from the area, which produced tension between the two nations for decades. 

“What really struck me about the Cod Wars example … is that you’re not talking about developing countries skirmishing—this was members of NATO that were in conflict with one another and almost came to a hot war,” Duffy said. He added that there are many conflicts centered on fisheries between countries like the U.S. and China in the present day, as well. 

The Scientific Arsenal: As climate threats on national security mount, the Trump administration is actively defunding research on the subject. In March, Defense Secretary Hegseth—a climate denier—announced that the agency canceled 91 social science-related research projects, which investigated everything from how climate change could influence global migration to how warming can lead to more instability in Africa, Reuters reported. 

Later that month, Hegseth issued a memo directing the Pentagon to review mission statements and planning documents to make sure there are no “references to climate change and related subjects.” However, the memo did include exceptions for efforts related to preparing military operations for extreme weather and related risks, according to documents reviewed by E&E News. The Department of Defense did not respond to a request for comment from ICN about the contract cancellations. Additionally, the Office of the Director of National Intelligence did not respond to a request for comment about why climate change was not included in this year’s annual threat assessment. 

Job and research cuts at other agencies could also inhibit the country’s ability to respond to climate shocks and threaten national security, experts say. For example, major staffing cuts at the National Oceanic and Atmospheric Administration in the last few weeks could affect the accuracy of weather modeling such as hurricane forecasts, as my colleagues Bob Berwyn and Lauren Dalban recently reported. A White House budget plan proposed earlier this week pitches similar cuts at NASA, though some Congressional Democrats are pushing back. 

“This is a generational crisis for American science,” the Smithsonian’s Duffy said. “Nature is complex, just like economies and societies are, and we have to understand it if we are going to roll with the punches and survive as a global civilization, frankly. And that depends on science.”

Cover photo:  In 2018, Hurricane Michael hit the Tyndall Air Force Base in Florida. Credit: BRENDAN SMIALOWSKI/AFP via Getty Images