Pentagon declares Anthropic a threat to national security

The Trump administration placed AI firm Anthropic on a far-reaching national security blacklist Friday, directing federal agencies to stop using its technology and banning any other company that does business with the military from working with it, effective immediately.

President Donald Trump blasted the artificial intelligence company as a risk to national security after a tumultuous week of negotiations between the start-up and the Pentagon.

“The Leftwing nut jobs at Anthropic have made a DISASTROUS MISTAKE trying to STRONG-ARM the Department of War, and force them to obey their Terms of Service instead of our Constitution,” Trump wrote in a post on his social media site Truth Social, using the administration’s preferred name for the Defense Department. “Their selfishness is putting AMERICAN LIVES at risk, our Troops in danger, and our National Security in JEOPARDY.”

Defense Secretary Pete Hegseth followed up late Friday, saying in a post on X that he was declaring Anthropic a supply-chain risk. “Effective immediately, no contractor, supplier, or partner that does business with the United States military may conduct any commercial activity with Anthropic,” Hegseth wrote.

Anthropic said it would fight the blacklisting in court. In a blog post late Friday, the company said that it believed the wide-reaching ban Hegseth described was not permitted by federal law and that the designation of the company as a supply-chain risk was “legally unsound.”

The company wrote that, “Designating Anthropic as a supply chain risk would be an unprecedented action - one historically reserved for US adversaries, never before publicly applied to an American company.” The unsigned blog post added: “We are deeply saddened by these developments.”

The dispute sprang from Anthropic resisting Pentagon demands that it allow the military to use its AI system, Claude, for any purpose permitted by the law. Anthropic had insisted on protections against its technology being used to power fully autonomous weapons or wide-scale domestic surveillance.

The conflict had reached an apparent impasse late Thursday after Anthropic CEO Dario Amodei wrote in a blog post that he would not concede to the Pentagon’s demands. Emil Michael, the Defense Department’s technology chief, shot back on X, calling Amodei a liar with a god complex in a late-night string of posts.

The supply-chain-risk designation issued by Hegseth late Friday was an extraordinary escalation, ranking a leading American AI company alongside the likes of Chinese and Russian firms seen as a danger to the United States.

It was unclear how easy it would be for government departments to move away from Anthropic’s technology, or for the company’s partners that do business with the Pentagon to cut ties. And the Pentagon did not explain the legal reasoning behind its claim that it could compel military contractors to immediately cease work with Anthropic.

Trump said he was allowing federal agencies a six-month period to transition off Anthropic’s technology, vaguely threatening more consequences for the company after that.

“Anthropic better get their act together, and be helpful during this phase out period, or I will use the Full Power of the Presidency to make them comply, with major civil and criminal consequences to follow,” he wrote.

Anthropic’s relationship with the Trump administration was already souring before its recent dispute with the Pentagon. While the company partnered with the president’s team to bring AI to the government, Amodei and Anthropic executives also clashed publicly with the White House, calling for regulations on AI and criticizing its decision to allow the export of advanced chips to China.

Experts said the Trump administration’s dramatic intervention Friday is likely to have ramifications for more than just the U.S. government’s relationship with Anthropic, potentially complicating the administration’s work with other AI developers, especially in relation to defense work.

As tech giants emerged as the nation’s most innovative companies over recent decades, they tended to stay away from working with the Defense Department. That has changed in recent years, with investors and engineers warming to the idea of collaborating with Washington.

“It has taken a lot to get to where we are now, such that leading lights of the U.S. tech industry are enthusiastically taking on national security work,” said Gregory Allen, a senior adviser with the Wadhwani AI Center at the Center for Strategic and International Studies and formerly a director at a Pentagon AI center. “That’s a night-and-day difference.”

Many researchers and engineers working on AI have long harbored concerns about their technology being used to power weapons or surveillance. The battle between Anthropic and the Pentagon has reawakened those concerns across the industry.

By Friday afternoon, more than 550 employees at Google and ChatGPT-maker OpenAI had signed an open letter in support of Anthropic’s position and calling on their bosses to stand up to the Pentagon. Earlier in the week, Jeff Dean, Google’s chief AI scientist, said he was opposed to the technology being used for surveillance and repeated his long-standing opposition to autonomous weapons. (The Washington Post has a content partnership with OpenAI.)

Just before 10 p.m. Eastern time on Friday, the CEO of Anthropic’s rival OpenAI, Sam Altman, wrote in a post on X that his own company had reached an agreement with the Defense Department to deploy its own technology in classified U.S. networks.

“Two of our most important safety principles are prohibitions on domestic mass surveillance and human responsibility for the use of force, including for autonomous weapon systems,” Altman wrote. The Pentagon “agrees with these principles, reflects them in law and policy, and we put them into our agreement,” he said.

It was not immediately clear why the Defense Department had agreed to those limits after attacking Anthropic for insisting on placing similar bounds on its own technology.

Elon Musk’s xAI could also benefit from Anthropic’s dispute with the Pentagon. Defense officials have said xAI has already agreed to the Pentagon’s terms for working on classified systems. The entrepreneur jumped on Michael’s social media thread Friday, saying “Anthropic hates Western Civilization.”

Although Anthropic has sought to position itself as the most safety-conscious of the major AI firms, it has also been enthusiastic about working with the military and intelligence agencies. The start-up struck a partnership during the Biden administration with Amazon and analytics company Palantir that allowed it to become the first of the companies to work on the classified systems where the government stores its secrets.

Under Trump, Anthropic landed a $200 million Pentagon contract and agreed to supply Claude to civilian agencies for a dollar.

Amodei said in his Thursday blog post that the company would work with officials to transition to a new AI provider if necessary. But that could prove to be costly and disruptive since Claude is already widely in use and viewed by experts as superior in some ways to its competitors.

The relationship between the Pentagon and Silicon Valley has soured at times before. In 2017, Google and the Defense Department began working on an AI project called Maven. But as more employees at the tech giant learned about the program, they raised objections internally, and Google ultimately pulled out of the work, introducing internal policies that prohibit use of its AI technology for weapons or surveillance.

Allen said that it took years to repair the relationship with the tech industry.

“We have been in such a better place in the past four years or so,” Allen said. “That’s a wonderful state of affairs. You don’t want to pointlessly light that on fire.”

Google last year dropped its restrictions on use of its technology for surveillance or weapons, saying companies based in democratic countries should serve national security clients.

Project Maven continued with other partners. Retired Lt. Gen. Jack Shanahan said this week that one of the companies involved is Anthropic.

CORRECTION: A previous version of this article incorrectly said that the Trump administration effectively banned companies that do business with the U.S. government from working with Anthropic. The administration banned companies that do business with the military from working with Anthropic.

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