Treasury Secretary Scott Bessent isn't mincing words about New York City Mayor-elect Zohran Mamdani. Speaking on CNBC's "Squawk Box" Tuesday, Bessent delivered what might be the most diplomatically brutal assessment possible: nice campaign, terrible ideas.

A Great Campaigner With Questionable Economics

Bessent was actually in the room when Trump met with Mamdani at the White House recently, and he came away impressed with at least one thing. "You've got to have some admiration," he said, crediting Mamdani for running "a great campaign" and calling him "clearly the leader of the Democratic Party now."

But here's the kicker. Bessent also called Mamdani "a young man with a lot of old ideas that have never worked." He threw down a challenge: "Point to one example where policies like his have led to anything other than a decline."

The Treasury Secretary drew a sharp line between campaigning and governing. "It's easy to run a campaign," he noted, but handling the "practical everyday" responsibilities of running America's largest city? That's an entirely different beast.

Despite the criticism, Bessent emphasized Trump's open-minded approach to the meeting. "I think it speaks to how open-minded the president is that he invited him," Bessent said, pointing out that even Chuck Schumer "never endorsed him" and may not have met with Mamdani at all. The administration's position appears to be: we think your ideas are wrong, but we want you to succeed anyway. "President Trump wants the best for New Yorkers," Bessent added.

Mamdani's Progressive Policy Blitz

Since winning the mayoral race earlier this month, Mamdani hasn't exactly backed away from his progressive platform. He's pushing ahead with proposals including free bus rides, free child care and a rent freeze on regulated apartments.

He wants to open five city-owned grocery stores, one in each borough, targeting neighborhoods with limited supermarket access. And last week, he proposed a 2 percentage point tax increase on income above $1 million, claiming it could generate billions to fund his various programs.

Not everyone's on board, though. New York Governor Kathy Hochul, who endorsed Mamdani during the race, has expressed reservations about certain proposals like the free bus rides, citing financial constraints. That's probably the kind of "practical everyday" reality Bessent was talking about.