Maybe the trouble started with the AI billionaire and the Silicon Valley chaos that followed talk of his infidelity, including with an alleged Chinese spy. Or maybe it was the Microsoft outage that, depending on how you looked at it, either cast millions of frustrated workers adrift or spared them from a daily, unrelenting electronic avalanche. But by Friday afternoon, when U. S. aviation authorities ordered the grounding of planes across the country, it felt to many that something was up. was...