Following up on this morning’s blog post, WSJ: Threat of California Billionaire Tax Draws Criticism From Ultrawealthy:

Washington Post Editorial Board: California will miss billionaires when they’re gone (Jan 1, 2026)

Many progressives think of taxation the way teenage boys think about cologne: if some is good, more must be great. California already reeks of overtaxation, but it’s thinking about trying out its most potent scent yet: a wealth tax. Just a whiff has some of the state’s wealthiest residents fleeing.

In 2012, California voters passed Proposition 30, increasing the marginal tax rate on high-income households up to 3 percent….

High earners responded by either leaving the state or reducing their taxable income. “These responses eroded 45.2 percent of state windfall tax revenues within the first year and 60.9 percent within 2 years,” economists Joshua Rauh and Ryan Shyu concluded in a 2024 paper.

But that history is not deterring the Service Employees International Union (SEIU), which represents hospital workers, from collecting signatures to put a measure on November’s ballot that would slap a one-time, 5 percent wealth tax on the state’s billionaires, with the revenue primarily dedicated to health care spending. This includes illiquid paper wealth, such as a founder’s share of a startup.

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