https://en.wikipedia.org/wiki/Defense_Production_Act_of_1950

Great article, it has a list of times it's been used to compel cooperation.

Ok. So what's the emergency prompting them to take control of Anthropic?

Further, why would they also accuse them of being a national security threat in the same breath? Seems like if they're a threat they're also not someone you want working on national security. Especially under duress. That feels like a bad combination.