On a Saturday morning in December 2022, Elon Musk summoned finance executives at Twitter, which he had bought six weeks earlier, to a conference call. Then he drilled into a spreadsheet that contained the social media company’s expenditures.

Elon Musk has slept on Tesla's factory floor and instructed SpaceX employees to walk out of meetings where they aren't adding value.

Musk's newfound influence in the Trump world comes as regulators are grappling with the myriad of cutting-edge technologies his companies are developing.