Of course Zohran Mamdani couldn’t manage a decent welcome for the king of England: That would’ve required maturity, grace and humility that our mayor just doesn’t have.

Mamdani did the absolute minimum to welcome King Charles to New York as he visited the city Wednesday, agreeing (belatedly!) to just one brief meeting with the monarch, at the 9/11 memorial — though the royal visited several sites across town.

Like any chief-executive job, New York’s mayor has occasional ceremonial duties — but Mamdani’s not interested in them, as they won’t bring many TikTok likes.

Showing respect for the king is showing respect for Britain, yet Mamdani couldn’t resist showing disrespect.

Past mayors have done their duty with British royals: Mayor Robert Wagner threw a ticker-tape parade on Queen Elizabeth’s arrival in the city in 1957; Mayor Abe Beame’s granddaughter greeted her with flowers as her ship sailed in two decades later.

But Mamdani couldn’t bother with any such gestures; he couldn’t even set aside his obsession with colonialism, telling reporters he hoped to push Charles “to return the Koh-i-Noor diamond,” a 105-carat gem originally from India and now on display at the Tower of London.

And he pointedly, mulishly, kept any mention of the king off his public schedule.

The point of the British crown is to represent that country beyond politics; the king’s visit is about our two nations’ deep bonds, a special relationship that has served both sides well for centuries.

But nothing is beyond politics for a modern progressive; every public event is simply an opportunity for divisive posturing.

Charles should probably be thankful the mayor didn’t try to arrest him, as he’s vowed to put Israeli Prime Minister Benjamin Netanyahu in cuffs.

Mamdani’s inexperience is no excuse for letting his personal passions blind him to the duties of his high office; it’s his addiction to performative displays that makes him such a clown.

At best, his youth means there’s a chance he’ll learn from his graceless mistakes, and do a bit better the next time he’s called to represent all the people of New York City.