“Move fast and break things,” a high-tech mantra popularized 20 years ago by Facebook founder Mark Zuckerberg, was supposed to be a rallying cry for game-changing innovation. It now seems more like an elegy for a society perched on a digital foundation too fragile to withstand a defective software program that was supposed to help protect computers — not crash them.

The worldwide technology meltdown caused by a flawed update installed earlier this month on computers running on Microsoft’s dominant Windows software by cybersecurity specialist CrowdStrike was so serious that some affected businesses such as Delta Air Lines were still recovering from it days later.

It’s a tell-tale moment — one that illustrates the digital pitfalls looming in a culture that takes the magic of technology for granted until it implodes into a horror show that exposes our ignorance and vulnerability.

“We are utterly dependent on systems that we don’t even know exist until they break,” said Paul Saffo, a Silicon Valley forecaster and historian. “We have become a little bit like Blanche DuBois in that scene from ‘A Streetcar Named Desire,’ where she says, ‘I have always depended on the kindness of strangers.’ ”