The reason was a conflict between Anthropic and the US Department of Defense. Amodei demanded guarantees from the Pentagon that Claude would not be used for mass surveillance of Americans or the creation of autonomous weapons under government contracts. He believed the AI was still too immature for this. The military viewed these demands as an attempt to dictate their terms.

"The US will not allow 'some radical leftist company' to dictate how the Pentagon conducts its business," Trump said.

Altman, incidentally, publicly supported Amodei yesterday and announced a partnership with the Pentagon. The WSJ reports (https://www.wsj.com/tech/ai/openais-sam-altman-calls-for-de-escalation-in-anthropic-showdown-with-hegseth-03ecbac8) that Altman handed the military a memo asking them not to demand AI companies comply with conditions that Anthropic didn't agree with.