The Pentagon is hoarding critical minerals that could power the clean energy transition

This story was originally published by Grist and is reproduced here as part of the Climate Desk collaboration.

Pete Hegseth, who has taken to calling himself the Secretary of War, says the Defense Department “does not do climate change crap.” Just last week, he asserted that the agency  “will not be distracted” by climate change or “woke moralizing.”

But a new report suggests that the Pentagon is engaging with the issue in one serious way: As it stockpiles dozens of critical minerals, it is threatening the energy transition by hoarding resources that could be used to decarbonize transportation, energy production, and other sectors.

President Donald Trump’s One Big Beautiful Bill Act allocated $7.5 billion to bolster the Pentagon’s reserves of critical minerals like cobalt, lithium, and graphite that are held in six depots nationwide, an effort supervised by the Defense Logistics Agency. Such materials are used in everything from jet engines to weapons systems and often are mined or processed in China or other nations. The materials in the stockpile are only accessible during times of declared war, or by order of the Undersecretary of War, a Defense Logistics Agency spokesperson said.

The report on potential peaceful uses for those materials was released by the Transition Security Project, which analyzes the economic, climate, and geopolitical threats posed by the US and British military. Lorah Steichen, a strategist who prepared the document, said America is essentially facing a choice between missiles and buses. The Pentagon’s planned cobalt and graphite stockpiles (7,500 metric tons and 50,000 metric tons, respectively) could electrify 102,896 buses — dwarfing the 6,000 or so currently operating in the US. Or they could be used to produce 80.2 gigawatt-hours of battery capacity, which is more than twice the energy storage the country has now. 

The International Energy Agency also has said such minerals could be used for peaceful ends, like building batteries, wind turbines, and other technologies underpinning the green transition. But designating a mineral as “critical” allows the government to fast-track mining and procurement for military ends. “The term ‘critical minerals’ originates out of military stockpiling—the criticality of a mineral is linked, in part, to its significance to national security,” Steichen said. 

The last time the Pentagon hoarded nonfuel materials was during the Cold War, when the government sought to create storehouses of industrial raw materials (like metals and agricultural supplies) and limit dependency on other nations. By the late 1990s, the United States began to see other countries—particularly those in the Caribbean—as generally reliable suppliers, and by 2003, the stockpile was reduced to nearly nothing. During Joe Biden’s presidency, there was some movement toward reviving the stockpile specifically to fight climate change. (That plan, according to a DLA spokesperson, never came to fruition.) This year, however, Trump’s One Big Beautiful Bill allocated $2 billion for expansion of the hoard, and $5.5 billion toward the supply chain infrastructure needed to secure those minerals.

Even some military and governmental experts have agreed that expanding the government’s stash is concerning. A Department of Defense report from 2021, for example, said that if the supply chain for rare earth elements—a subset of critical minerals—is disrupted, “the civilian economy would bear the brunt of harm.” 

“The point here is to push back against some of the bellicose associations of critical minerals and the different assumptions that go into that,” Steichen said. “What are the materials that are actually necessary for the energy transition, compared to this other definition of criticality?”

Militaries aren’t required to report their greenhouse-gas emissions—and the US military, in particular, is the single largest institutional emitter of greenhouse gases in the world and accounts for about 80 percent of the US government’s overall emissions. They also generally aren’t required to report the quantities of minerals they’re procuring and using. 

Julie Klinger, a geographer at the University of Wisconsin who studies extraction and resource frontiers, says these things deserve more scrutiny. “Particularly as we’re moving into a time where there is much more overt taxpayer-funded support of critical mineral mining and processing projects, the taxpayer does need to have quite a bit more information,” she said. 

The Defense Logistics Agency made an unusual admission when it released exactly how much cobalt and graphite it is working to procure. Often, Steichen said, such information isn’t easily available to the public. Some numbers are known—for example, a single F-35 warplane reportedly requires about 920 pounds of rare earth minerals for its engines and weapons-tracking systems. But across the Pentagon’s vast web of suppliers, it’s not clear where all the minerals are going.

“It creates an accountability gap and obscures a clear understanding of military resource use,” Steichen said. “We know this is the amount they’re seeking to stockpile—but we don’t know the specific volume of those materials going into different military sectors, or to different military contractors.” 

The Pentagon has been investing in mines that produce some of these minerals in places like Alaska, Idaho, and Saudi Arabia. Right-wing think tanks like the Heritage Foundation and Rand have spent the past five years urging the government to stockpile these materials to ease its reliance on adversaries like China, which currently dominates the global critical minerals market. 

Researchers like Klinger question the federal decision to prioritize military stockpiling—in part because most critical minerals, like graphite, have the potential to be recycled when they’re used in batteries, but are lost when made into, say, bombs. One thing sustaining demand for fossil fuels is the fact that they are consumed through use, Klinger said. Critical minerals like lithium and cobalt, on the other hand, can, when used for civilian purposes, be reclaimed or recycled. 

“The one application of critical minerals that destroys them through use is literally blowing them up,” she said. “Are these critical minerals going into energy technologies, which then have a whole host of societal benefits, or are they simply being dug out of the ground in one place to be blown up in another place?”