New York Mayor Zohran Mamdani speaks during an address on April 12, in New York. The mayor targeted Citadel LLC founder Ken Griffin as an example of a billionaire who should be tagged with the city’s proposed new pied-à-terre tax.Andres Kudacki/The Associated Press
Gus Carlson is a U.S.-based columnist for The Globe and Mail.
It’s hard to believe New York Mayor Zohran Mamdani has not heard the proverb that warns to never bite the hand that feeds you. Or maybe he has and just doesn’t care.
How else to explain the progressive social democrat’s harebrained decision to pick a fight with one of the financially strapped city’s most generous benefactors?
Consistent with his campaign promise to raise taxes on the city’s wealthiest individuals and more profitable companies, the mayor has targeted Citadel LLC founder Ken Griffin as an example of a billionaire who should be tagged with the city’s proposed new pied-à-terre tax on non-primary residences valued at more than US$5-million.
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Mr. Mamdani recently posted a video of himself outside Mr. Griffin’s US$238-million Manhattan apartment, calling out the financier as the worst kind of offender.
It was sophomoric – and a little creepy – political theatre. And it backfired.
Citadel countered with a statement reminding the mayor that while Mr. Griffin’s primary residence is in Miami, he is a huge benefactor to New York, including backing a US$6-billion redevelopment project in Manhattan that will create more than 20,000 jobs – 6,000 in construction and 15,000 permanent roles.
Citadel also reminded Mr. Mamdani that it employs 2,500 people in New York. Over the last five years, its employees have paid US$2.3-billion in city and state taxes and contributed hundreds of millions of dollars to city charities. More than 200 employees sit on the boards of New York charitable foundations, it said.
Personally, Mr. Griffin directed US$650-million in charitable gifts to support New York anti-poverty organizations, charter schools, hospitals and cultural institutions.

Founder and CEO of Citadel Ken Griffin gestures as he speaks during the World Economic Forum (WEF) annual meeting in Davos on January 21, 2026. The World Economic Forum takes place in Davos from January 19 to January 23, 2026. (Photo by Fabrice COFFRINI / AFP via Getty Images)FABRICE COFFRINI/AFP/Getty Images
The company hinted that the mayor’s comments might prompt Mr. Griffin to pull out of the redevelopment project, killing the jobs.
Why did Mr. Mamdani do it? Maybe his staff didn’t do their homework on Mr. Griffin before they used him as the poster boy for Mr. Mamdani’s tax-the-rich campaign. Or, more likely, like so many extremists of any stripe, the mayor’s ideological and political ambition trumps the economic reality of his actions.
The city’s economy can’t afford the mayor’s antics. New York has been bleeding wealthy individuals, companies and jobs for some time.
A pre-election report by the Partnership for New York, a powerful bloc of major New York companies, showed more than 150 companies had left the city in the last few years because of rising taxes and stifling regulation. With them went tens of thousands of jobs, trillions of dollars in assets and countless billions in tax revenue.
That exodus has accelerated in the first few months of Mr. Mamdani’s term.
This week, investment firm Charles Schwab said it was moving its headquarters from Manhattan to New Jersey.
Jamie Dimon, the outspoken chief executive of JPMorgan Chase, has said repeatedly the situation has become so acute that companies face hard decisions about staying. He said his firm now has more employees in Texas than in New York.
Mr. Dimon also hinted that he may not have greenlit the firm’s new Manhattan headquarters several years ago if he had known then what Mr. Mamdani would be doing now.
Mr. Mamdani said this week the city is in a fiscal crisis, with heavy debt, rising expenses and falling revenues. And he has asked the state for help.
Democrat Governor Kathy Hochul has run hot and cold on Mr. Mamdani’s target-the-rich ambitions, though she seems to support his pied-à-terre tax.
In the last few months, she has done a bizarre flip-flop on the exodus from New York to low-tax states. She first railed against those who moved to Florida and scolded them for not sharing New York’s “values.” Recently, she made a public plea for them to come back and, using one of the left’s favourite weasel phrases, pay their fair share.
At a recent news conference, Mr. Mamdani made fun of Margaret Thatcher’s infamous jab that socialism is fine but eventually you run out of other people’s money – and then boasted about using US$30-million in taxpayer money to build his “free” grocery store – 10 times what a private chain would spend on a single store.
Ms. Thatcher’s quip probably isn’t so funny any more to Mr. Mamdani, who is watching the wheels come off his socialist agenda because he is quickly running out of feeding hands to bite.