Appearing before a meeting of the National Governor’s Association on Saturday, Tesla CEO Elon Musk described artificial intelligence as “the greatest risk we face as a civilization” and called for swift and decisive government intervention to oversee the technology’s development.

“On the artificial intelligence front, I have access to the very most cutting edge AI, and I think people should be really concerned about it,” an unusually subdued Musk said in a question and answer session with Nevada governor Brian Sandoval.

Musk has long been vocal about the risks of AI. But his statements before the nation’s governors were notable both for their dire severity, and his forceful call for government intervention.

“AI’s a rare case where we need to be proactive in regulation, instead of reactive. Because by the time we are reactive with AI regulation, it’s too late,” he remarked. Musk then drew a contrast between AI and traditional targets for regulation, saying “AI is a fundamental risk to the existence of human civilization, in a way that car accidents, airplane crashes, faulty drugs, or bad food were not.”

Those are strong words from a man occasionally associated with so-called cyberlibertarianism, a fervently anti-regulation ideology exemplified by the likes of Peter Thiel, who co-founded Paypal with Musk.

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Musk went on to argue that broad government regulation was vital because companies are currently pressured to pursue advanced AI or risk irrelevance in the marketplace:

That’s where you need the regulators to come in and say, hey guys, you all need to just pause and make sure this is safe . . . You kind of need the regulators to do that for all the teams in the game. Otherwise the shareholders will be saying, why aren’t you developing AI faster? Because your competitor is.

Part of Musk’s worry stems from social destabilization and job loss. “When I say everything, the robots will do everything, bar nothing,” he said.

But Musk’s bigger concern has to do with AI that lives in the network, and which could be incentivized to harm humans. “[They] could start a war by doing fake news and spoofing email accounts and fake press releases, and just by manipulating information,” he said. “The pen is mightier than the sword.”

Musk outlined a hypothetical situation, for instance, in which an AI could pump up defense industry investments by using hacking and disinformation to trigger a war.

“I’m against overregulation for sure,” Musk emphasized, “But man, I think with we’ve got to get on that with AI, pronto.”

Musk’s comments on AI only took up a small part of the hour-long exchange. He also speculated about the future of driverless cars and space travel, and mourned that meeting the sky-high expectations surrounding him was “quite a difficult emotional hardship” and “a whole lot less fun than it may seem.”