California Gov. Gavin Newsom is calling for a national “billionaires' tax” and suggests the U.S. government should own a stake in AI companies. He warns that urgent reform is needed to prevent wealth concentration from harming democracy. Newsom's proposal aligns him with the populist left as he considers a 2028 presidential run. He proposes a minimum tax on those with over $100 million in net worth and wants to prevent the wealthy from borrowing against stock portfolios tax-free. Newsom opposes a California measure taxing billionaires, arguing the issue should be addressed federally to prevent billionaires from leaving the state.