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- Caroline Mercer via Fast Company
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- Politics·4 min to read
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Bill Ackman Backs Trump's Iran War and Faults Mamdani Over New York's Business Climate
ReBill Ackman Backs Trump's Iran War and Faults Mamdani Over New York's Business Climate
Hedge fund founder Bill Ackman used a New York stage to defend the Iran war and criticize Mayor Zohran Mamdani's pied-à-terre tax, saying the mayor has driven productive residents to Miami.
Bill Ackman, the billionaire founder and chief executive of Pershing Square Capital Management, publicly defended President Trump's war with Iran and sharply criticized New York City Mayor Zohran Mamdani, arguing that the mayor's policies have pushed the city's most productive residents toward Miami and other destinations.
Speaking at the Fast Company Innovation Festival in New York on September 15, Ackman told Fast Company CEO Stephanie Mehta that he was «comfortable being in the minority» on the Iran conflict. «I'm a believer that the President did the right thing in going to war with Iran,» he said, describing the campaign as a necessary step to destroy Iran's nuclear capability, its ballistic missile program, and a government he said had killed a meaningful share of its own population for protesting. «If we didn't do it, it could be an existential threat to the United States,» he added.
Ackman acknowledged that the war has carried economic costs, pointing to higher energy prices as the main consequence. He said the administration is working to open the Strait of Hormuz and find alternative energy sources to keep gasoline and other prices lower. Energy costs, he noted, feed into transportation, materials, and even fertilizer, driving inflation that weighs most heavily on lower-income groups.
The appearance marked a public doubling down on positions Ackman has promoted to nearly three million followers on X, where he posts daily and has become a vocal supporter of conservative policies since endorsing Trump in 2024 after decades of backing Democratic candidates. His online commentary has ranged from support for artificial intelligence in New York City schools to praise for Elon Musk and repeated criticism of Mamdani.
On the mayor, Ackman was direct. «Socialism is not the right strategy for New York,» he said, calling for incentives and tax design that promote business development. He singled out Mamdani's pied-à-terre tax, which took effect July 6 and applies to non-primary residences worth more than $5 million. Ackman argued the levy could deter wealthy figures such as billionaire Ken Griffin from bringing business to the city.
Earlier this year, Mamdani promoted the pied-à-terre tax in a video filmed outside Griffin's apartment. Ackman said that approach was counterproductive. «You want to encourage people like that to be here, as opposed to doing a video in front of their apartment and calling them out,» he said. «It's a huge mistake. The mayor has scared away some of the most productive New Yorkers to other places like Miami.»
Ackman framed his criticism as aimed at the mayor rather than the city itself, saying he is «not critical of New York City.» His remarks add a prominent business voice to the debate over New York's tax policy and its ability to retain high earners, a question with direct consequences for the city's revenue base and its standing as a corporate hub.
He also noted one disagreement with Trump: the president's recent pledge to give Americans $5,000 if Republicans keep control of Congress. Even so, Ackman said, «every president is flawed in varying ways.»
The comments place Ackman at the center of two overlapping political conversations — the economic fallout of the Iran conflict and the direction of New York City under Mamdani — as he continues to use his platform to shape debate well beyond the hedge fund industry.
