There's a classic Silicon Valley story: a startup grows, creates jobs, and then, when it gets big enough, it packs up and moves to Texas. The latest chapter in that saga is playing out in California's political arena, where a proposed tax on billionaires has sparked a war of words between a venture capitalist and a congressman.

Josh Elman, a partner at Andreessen Horowitz and a former Apple product manager, took to X to ask a pointed question: "Why do California politicians want to push away startups?" He argued that startups can create "incredible numbers of new jobs and opportunities" in a short time, and then reminded everyone of two high-profile departures: "We already lost Tesla HQ and SpaceX HQ due to political shenanigans."

Elman was responding to Rep. Ro Khanna (D-Calif.), who had defended the billionaire-tax proposal. Khanna, a self-described "progressive capitalist," argued that 72% of billionaire wealth is held in public stock and said he wants "a new social contract for this country" that works for everyone, not just the capital class.

The exchange comes as California voters prepare to decide on a November ballot measure that would impose a one-time 5% tax on residents worth more than $1 billion. The tax, backed by SEIU Healthcare Workers West, could raise an estimated $100 billion for healthcare. But it's facing fierce opposition from some of the state's most prominent figures.

Mark Cuban, the billionaire investor, has warned that he might make leaving California a prerequisite for some startup investments if the tax passes. His blunt assessment: "ideology is not a strategy."

Gov. Gavin Newsom (D) also opposes the measure, arguing that wealthy residents could simply relocate, weakening future tax collections. The concern isn't hypothetical: California's top 1% of earners, about 175,000 taxpayers, contribute nearly half of the state's personal income tax revenue. The nonpartisan Legislative Analyst's Office estimates the proposal could raise tens of billions initially, but later reduce annual income-tax revenue by hundreds of millions.

The stakes are high, and the history is telling. Tesla moved its headquarters from Palo Alto to Austin in 2021 after Elon Musk criticized California's regulations and taxes. SpaceX followed suit in 2024, relocating from Hawthorne to Starbase, Texas, after Musk called a California law the "final straw."

But it's not as if these companies have completely abandoned the Golden State. Tesla later established its engineering headquarters in Palo Alto and still operates its Fremont factory. And California remains an economic powerhouse, producing nearly 15% of U.S. GDP.

Elman, who joined a16z to focus on consumer technology and AI, framed the debate around startup growth: policy choices, he argues, can shape where founders decide to build and hire. It's a reminder that for all the talk of tax fairness and social contracts, the decisions made in Sacramento can have real consequences for the state's entrepreneurial ecosystem.

As the November vote approaches, the question isn't just whether the tax will pass, but whether California can afford to lose more of its brightest minds and biggest companies. The answer may depend on whether politicians listen to the likes of Elman, or dismiss his concerns as "political shenanigans."