With each passing day, Gotham — supposedly, the world capital of capitalism — seems to be marching ever closer to . . . socialism.

All while its corporate titans remain quiet as church mice.

If they want to save their businesses, the economy — heck, New York! — it’s long past time they speak out. Publicly.

For years, these leaders (with a few exceptions, like Bill Ackman) have taken a “go-along-to-get-along” approach.

Even the Partnership for New York City has long placed its friendship with the administration over the interests of its corporate members.

Perhaps business leaders fear retribution from City Hall or Albany. Maybe they’ve got deals with government officials they don’t want to disturb — or want to keep under the radar.

For too long they have wrongly thought that dealing behind the scenes works.

But we have seen for more than a decade now the creep, creep, creep of progressivism and now socialism take hold in New York City. What they have been doing is plainly not working. 

Under socialist Mayor Zohran Mamdani and weak-kneed Gov. Kathy Hochul, the situation is growing dire.

The business leaders need to realize: Zo’s tax-the-rich mob is coming for . . . them.

Look at how Hizzoner proudly doxxed billionaire Ken Griffin — using his $238 million penthouse as a backdrop in a “tax the rich” video unveiling Hochul’s pied-à-terre tax.

That was thoughtless and juvenile posturing by Mamdani: For starters, Citadel and its employees paid nearly $2.3 billion in city and state taxes over the past five years, plus Ken Griffin has made $650 million in philanthropic contributions — to cancer care, charter-school education, museums and cultural arts in the city.

Zo’s zinger could wind up costing the city 6,000 temporary construction and 15,000 permanent jobs, plus $6 billion in construction costs if Griffin decides to cancel an office tower he’s planning.

Ex-Gov. David Paterson likened the mayor’s stunt to something a mobster would do in “The Godfather.”

Yet even then, Griffin didn’t personally make a stink; instead, one of his top execs sent out a company-wide email defending the boss and hinting that he might nix the project.

Griffin — and every other business leader who hopes the city remains a viable place for their companies — ought be out there, loud and proud, making their case to the public: screaming about how many people they employ and how many billions they invest in construction projects (which provide even more jobs).

They should describe how their enormous corporate budgets and thousands of employees help keep the local economy afloat — whether by spending on Ubers, restaurants, lawyers, accountants or night cleaning crews.

And they should remind folks of the huge amount of taxes they and their workers already fork over to the city and state.

The securities industry alone, per state Comptroller Tom DiNapoli, accounted for 8.4% of city tax revenue last year, and 19.4% of the state’s.

Yes, New York’s moguls can leave the city; many already have, and others may soon join them.

But businesses don’t really want to leave.

And if they can convince the public they’re needed, maybe they won’t have to.