Joe Gebbia, a confidant of the technology billionaire and a Tesla director, is also a leader of the federal cost-cutting team. The fight might put him in a bind.

Trump late Monday night fought back, suggesting his administration may investigate Musk’s companies’ massive government contracts. On Tuesday at the White House, Trump said Musk risked losing “a lot more” than government subsidies and threatened that the Department of Government Efficiency that Musk once led may “go back and eat Elon.”