After single-handedly remaking the auto industry, social media and the global space race, Elon Musk is now turning his attention, and personal fortune, to politics. Over the past few months, he became one of the most influential figures in the race for president, and on Tuesday Donald J. Trump tapped him to help lead what the president-elect called the Department of Government Efficiency, Kirsten Grind and Eric Lipton, investigative reporters for The Times, explain what exactly Musk wants from the new president, and why he is so well placed to get it. Guest: Kirsten Grind, an investigative business reporter at The New York Times. Eric Lipton, an investigative reporter at The New York Times.