United Airlines CEO Scott Kirby collected roughly $32.3 million in total compensation last year, according to Fortune's reporting on the carrier's proxy statement. Yet the executive argues that people in his position should be paying more—starting with a tax on the wealth they already hold.

In a wide-ranging interview with The New York Times in mid-October, Kirby described wealth inequality as something that "has become a danger to our society" and called for a national wealth tax, along with inheritance taxes that "get close to 100% at some level." "I would pay them," he added.

The remarks drew swift pushback, much of it aimed at his paycheck. Fox Business asked United how Kirby squared his pay with his warnings about inequality; the company did not respond.

Days later, Kirby doubled down on CNBC's Squawk Box, framing the proposal as a matter of fairness.

"I think a wealth tax… is just about fairness…. If you're wealthy enough, you can put money aside, and by the way, I think it would apply to me, put money aside, let it grow forever, never realize income on it, you can let it grow forever and it never gets taxed," he said.

That dynamic—the ability to hold appreciating assets without ever realizing taxable income—is the gap Kirby wants to close. The federal system is built around income rather than net worth: in 2025, the top rate of 37% applied to single filers' taxable income above $626,350, according to the IRS. Investments that rise in value but are never sold never trigger a tax bill. That gap has reached Washington before: beginning with his fiscal 2023 budget, President Joe Biden proposed a billionaire minimum income tax aimed at households worth more than $100 million, though it never became law. And in 2024, the Supreme Court, in Moore v. United States, upheld a tax on certain undistributed corporate earnings without settling whether income has to be "realized" to be taxed under the Constitution—leaving that question open for any future wealth tax fight.

Kirby's stance stands out because of who holds it. He runs a company ranked on the 2026 Fortune 500 that brought in $59.1 billion in revenue last year. He stressed that these were personal views and that he has no interest in politics or policymaking. If it were up to him, he said, he would prefer a system "where we had lower income taxes, and higher taxes, or some kind of taxes, on the gain in wealth." He is not the first person of means to make that argument: investor Warren Buffett has pressed for years to tax the ultra-rich more heavily, and the Patriotic Millionaires, a group of wealthy Americans, has lobbied Congress for the same.

The case against taxing wealth

In practice, the idea draws pointed objections. Mariana Trujillo, managing director of government finance at the Reason Foundation, a libertarian-leaning think tank, tells Fortune the tax would undercut the very growth it is meant to share.

"Taxing accumulated wealth discourages investment and entrepreneurship — the very forces that have made our lives better than those of our grandparents and great-grandparents. Economic progress, not the state, has driven improvements in our material condition. A wealth tax discourages the very thing it aims to promote," she says.

Trujillo drew a sharp line between the two ideas Kirby floated. An inheritance tax strikes wealth once, when it changes hands. An annual wealth tax hits it every year, and she argued that recurring exposure gives the wealthiest Americans—and their capital—a reason to leave.

"An annual wealth tax is entirely different from an inheritance tax…. People move out of states and countries for tax reasons. National wealth taxes failed in Europe, where countries including France, Sweden, and Germany abandoned them amid concerns about capital flight, administrative costs, and disappointing revenues."

A handful of European countries have held on: Norway, Spain, and Switzerland still levy net wealth taxes, according to the Tax Foundation. Administration is part of the challenge, too: a wealth tax would require governments to put a value every year on assets that rarely trade—stakes in private companies, art, real estate—one of the cost concerns behind Europe's repeals.

Trujillo also had a message for Kirby himself. "If Kirby believes his wealth could be better used to improve others' lives, he is free to put it toward that purpose," she said. "But I hope he recognizes that his compensation reflects the perceived value of his contributions to his company and, therefore, to society at large. Wealth does not need to be redistributed to be productive; it is already the result of creating value for others."

California voters reject a billionaire tax

Kirby has argued that a state-by-state approach is doomed, which is why he favors a federal version. "We should have a national wealth tax—it won't work by state because people will just move," he told the Times, as Fortune reported.

California just tested a state version. In the Nov. 3 election, voters rejected Proposition 40, the so-called billionaire tax, which would have imposed a one-time 5% tax on the net worth of state residents worth more than $1 billion. The Associated Press called the race on Nov. 9, with 52.8% of voters opposed, according to CalMatters.

The measure had high-profile backers, including six Nobel Prize–winning economists who argued it could kick-start similar efforts elsewhere. But opponents spent about $378 million against it, while the yes campaign raised $33.5 million, and Silicon Valley voters broke against it even as Los Angeles and San Francisco voted yes.

Trujillo read the result as a verdict on the idea itself. "California's wealth tax proposal failed at the ballot box for good reasons: first, because voters recognized it may reduce government revenue as people leave, and second, because they saw it as discouraging investment and innovation, which make our lives better."

Where the idea goes from here is unsettled. Federal wealth tax proposals, including plans floated by Senators Elizabeth Warren and Bernie Sanders, have stalled in recent Congresses, and versions of the concept have resurfaced in budget debates and statehouse proposals over the past decade.

For his part, Kirby said the emails he received about his comments split about evenly between support and criticism. If California's outcome is any guide, the rest of the country isn't far off.

This story was originally featured on Fortune.com.