By James Fanelli

After Zohran Mamdani takes over running the country's largest city on Thursday, the 34-year-old Democratic socialist and relative political newbie will face a series of crucial early tests.

As New York City mayor, Mamdani plans to move forward with delivering on an ambitious affordability agenda while overseeing a vast municipal bureaucracy. Wall Street and real estate bigwigs have serious concerns that his administration will enact policies that upend the city's economy and reverse a recent crime drop. Meanwhile, his backers on the left expect him to deliver on his promise to freeze rents, create a free bus service and expand free child care.

Here is a look at the biggest challenges Mamdani faces in the coming months.

A steep learning curve

Mamdani takes office with a relatively thin résumé. Over the past four years, he served as a state assemblyman, representing parts of Queens. Before that, he tried his hand at rapping and worked as a foreclosure-prevention counselor. Some business leaders question whether he has the management chops to run a juggernaut like New York.

Political consultant Jon Paul Lupo said picking the right people to staff the administration helps. "The scale of running the government for anybody is a massive shift in responsibility," said Lupo, who served as a senior government official in former Mayor Bill de Blasio's administration.

Most New Yorkers want above all for the trash to get picked up and for other government services to run smoothly. Mamdani hired some steady hands to take the lead on those operations, including his choice of first deputy mayor, Dean Fuleihan, a longtime civil servant in the de Blasio administration. But if New York gets hit with a snowstorm early in his administration, the new mayor could quickly take flak if the streets aren't plowed fast enough.

A costly agenda

Mamdani's supporters will demand results on his costly affordability agenda, but he won't have an easy time finding funding. His proposal for a universal child-care program covering infants through 5-year-olds would cost $6 billion annually, according to his campaign's estimate. And his vision for a free bus system would be nearly $800 million a year.

Mamdani wants to raise taxes on corporations and the city's wealthiest to cover expenses, but state lawmakers and Gov. Kathy Hochul would need to approve the increases. Hochul, a Democrat who is up for re-election in 2026, has said she opposes raising income taxes but signaled an openness to changes to corporate taxes.

The new mayor will likely focus efforts on getting some part of his child-care plan passed, as it carries the broadest appeal and can be pitched as an economic boost to employers.

Winning over business leaders

Members of the business community have fretted over the cost of Mamdani's agenda and its reliance on proposals to increase taxes on corporations and millionaires. Business leaders and rank-and-file police officers also have been troubled by his past comments about defunding the New York Police Department and plans for the police force, including creating a department of mental-health specialists who respond to certain 911 calls.

Mamdani persuaded NYPD Commissioner Jessica Tisch, a respected civil servant who has ties to the business world, to remain in her post. He also hosted roundtables with business leaders in recent weeks to discuss affordable housing and child care.

Despite his overtures, many executives still want to see more people from the private sector in his administration.

Stemming antisemitism

Mamdani's openly critical views of Israel have left Jewish New Yorkers on edge that he will fail to protect them from antisemitic attacks. He has called for a free Palestine, doesn't acknowledge Israel's right to exist as a Jewish state and accused the country's government of genocide.

"We've never had a mayor in New York City who has believed these things, and so there is a high degree of anxiety in the New York Jewish community," said Rabbi Ammiel Hirsch, president of the New York Board of Rabbis.

The incoming mayor made an early misstep with one of his new administration hires. Catherine Almonte Da Costa resigned quickly after Mamdani named her director of appointments, when the Anti-Defamation League identified antisemitic social-media posts she made years earlier, including referring to "money hungry Jews."

Hirsch and other rabbis met with Mamdani in December and urged him to refrain from anti-Israel rhetoric and to forgo a campaign commitment to order the arrest of Israeli Prime Minister Benjamin Netanyahu on a warrant from the International Criminal Court if he visits New York. In media interviews after the meeting, Mamdani said his positions on Israel haven't changed.

After the recent mass shooting during a Hanukkah gathering at Bondi Beach in Australia, Mamdani reiterated his commitment to the city's Jewish community. "When I am mayor, I will work every day to keep Jewish New Yorkers safe -- on our streets, our subways, at shul, in every moment of every day," he said.

Avoiding a Trump takeover

Mamdani appeared to have defused a potential federal takeover of New York City when he met with President Trump in November.

The two men took shots at one another over the past year but set aside their differences at the Oval Office sit-down. Trump commended Mamdani on his mayoral campaign and said he had high hopes for New York City. The cheerful tone was in contrast to previous Trump comments calling Mamdani a communist and threatening to deploy the National Guard to New York if he won the mayor's race.

While tensions have cooled for now, many believe the threat of Trump interfering in the city still exists. The city relies on billions of dollars in federal funding, which Trump could try to cut off if he were unhappy with the new mayor. Meanwhile, many Mamdani supporters voted for him because of his pledge to stand up to Trump and protect immigrants. A showdown between the Mamdani administration and federal law enforcement could provoke the president.

Write to James Fanelli at james.fanelli@wsj.com

(END) Dow Jones Newswires

December 31, 2025 05:00 ET (10:00 GMT)

Copyright (c) 2025 Dow Jones & Company, Inc.