Not since Philippe Petit stepped onto a wire surreptitiously rigged between the towers of the late, lamented World Trade Center in 1974 has there been a tightrope walk as perilous and as public as Ivanka Trump’s.


It’s hard enough trying to be Queen of Manhattan in the 21st century, when the fame factory of social media has scrambled the delicate balance of wealth, glamour and ambition required to wear the crown. Over the past year, Ivanka’s social climb has been further complicated by business woes, legal thickets and - most of all — her father’s snatching of the presidency, which has turned the Trump name to poison in chic society.


Those of us who don’t belong to Manhattan society (meaning nearly everyone) might wonder whether queens are necessary in the first place. But through reigns of terror and periods of grace, matriarchs have ruled for nearly 150 years over America’s island principality between the East River and the Hudson. Caroline Astor is often cited as the first Queen of Manhattan. The Gilded Age made overnight millionaires, but only Mrs. Astor could make a rich person into a socialite. Her guest list was law — at least until she met Alva Vanderbilt.


Alva, an Alabama native with the bearing of a linebacker, usurped Astor’s crown and raised the stakes for future queens. Where Astor reigned in passive silence from a divan raised above her ballroom floor, Vanderbilt was an activist monarch. She led suffrage rallies and organized pro-labor fundraising events (when she wasn’t summering at her Newport mansion, where even the driveway was Italian marble). But her greatest achievement may have been her daughter Consuelo, a slender beauty whom Alva forced to marry the Duke of Marlborough, forever infusing New York society with cosmopolitan worldliness and a bias in favor of the comely.


Since those days, presiding over Manhattan has been a balancing act: a queen must be famous and mysterious at the same time; scheming in private but serene in public; always busy but never tied down. The best of them — Babe Paley, Jackie Onassis — know everyone, yet remain somehow unknowable themselves.


All true of Ivanka, who appears to combine the grit of Vanderbilt with the swanlike elegance of Paley, of whom Truman Capote observed that her only flaw was her perfection. But perfection is a higher bar for a woman today than it was in Paley’s 1960s. Today’s Queen of Manhattan needs more than looks and money. She must be an entrepreneur, a TED-talker, a woke woman and a mother, climbing the best-dressed list even as she floats somehow above the world on a raised platform.


What this looks like in real time Trump demonstrated this last week. A post to her Instagram feed (she has more than 4 million followers) showed her stretched out on a bed for story time, surrounded by her three perfect children. “I’m looking forward to visiting Japan, but sure will miss these three!” Queen Mommy chimed. The next we knew, she was smiling upon arrival halfway around the world, her sunglasses opaque, her bow-topped shoes entrancing. Then it was on to Toyko for a speech to the World Assembly for Women, where she dwelled on the importance of opening traditionally male-dominated occupations in science, technology, engineering and math.


“Female and minority participation in STEM fields is moving in the wrong direction,” the Visionary Queen observed, now clad in a pink suit that managed to be at once businesslike and flashy. Fashion websites and news websites tracked her moves with equal intensity — the former telling readers where to buy her outfits, the latter reporting that Ivanka would quickly return to the United States to take up the job of tax reform.


This is a long way from 1980s New York, with Nan Kempner and Pat Buckley trading sly jokes between graceful puffs on their cigarettes, and just as far from the glitz and ditz of a decade ago, starring Paris Hilton and Tinsley Mortimer. It’s a good fit for today’s Manhattan, except for one problem: The Trump name is like a curse throughout the realm.


Her apparel business has been buffeted by anti-Trump boycotts and scrutiny of her China ties. Her husband, Jared Kushner — the silent Ken to her Everything Barbie — is hampered by ethics watchdogs in his desperate attempt to bail out a family-owned skyscraper and at the same time under pressure from Special Counsel Robert Mueller’s investigation. Adding insult to injury, her father is said to be blaming Kushner’s bad advice for some of his own worst decisions, egged on by Javanka-hating Svengali Stephen Bannon.


That’s a fine how-do-you-do from a father who knows, down deep, that he alone may keep Ivanka from the throne. “If she weren’t my daughter, it would be so much easier for her,” the president has said. That wasn’t always true, but it is now.


Drehle writes a twice-weekly column for The Post. He was previously an editor-at-large for Time Magazine, and is the author of four books, including “Rise to Greatness: Abraham Lincoln and America’s Most Perilous Year” and “Triangle: The Fire That Changed America.”