After failing to block from the ballot a measure that would enact a billionaire tax in his state, California Gov. Gavin Newsom is now proposing a national wealth tax of his own.

In a lengthy Substack post and video released Friday morning, Newsom — who opposes a proposed one-time levy in his own state as he mulls a 2028 presidential run — said he instead supported a more expansive plan.

His proposal would create a minimum tax on billionaires and a national public equity fund whereby Americans would own a stake in the artificial intelligence industry, as well as close tax loopholes for the ultra-wealthy. Newsom’s proposal would require billionaires and those with a net worth of at least $100 million to pay a minimum tax.

“When 10% of the people in this country own two-thirds of the wealth, when we have minted the first trillionaire in human history, and yet your wages have stagnated, and your healthcare costs have skyrocketed, something is fundamentally broken,” Newsom wrote. “Over the decades, the American economy has been engineered for the very top, a story as old as time: Money buys influence, and influence rewrites the rules. Those rewritten rules funnel even more wealth to the few. Under this weight, democracy itself starts to buckle.”

Newsom’s proposal comes as he positions himself for a 2028 White House bid, with potential presidential hopefuls well aware of what is top of mind in the party. The Democratic base is increasingly agitating for its leaders to do more to address the nation’s wealth disparity, as the average American struggles to pay for the rising costs of food and fuel.

Newsom said his opposition to California’s billionaire tax proposal is grounded in where the money would be spent.

The California initiative would implement a one-time 5% tax on the assets of Californians whose net worth exceeds $1.1 billion. It would require the state to spend 90% of the new revenue on healthcare, with the remaining 10% split between education and food assistance programs.

Xavier Becerra, the leading candidate to succeed Newsom as governor and the former U.S. health secretary, also opposed the California billionaire tax proposal. Other prominent Democrats in the state — including Rep. Ro Khanna, another potential 2028 presidential candidate, and Tom Steyer, a billionaire activist who just lost a bid for governor — have backed the effort.

Newsom also cast the other part of his proposal, the AI equity fund, in part as a benefit for Americans whose jobs are cannibalized by the rapidly evolving technology.

“We need to ensure every American owns a stake in the future being built by AI through a national public equity fund that takes a major stake in the new economy,” Newsom wrote. “As artificial intelligence reshapes the country, every American should own a piece of the future it builds.”