The sudden collapse last fall of a string of American companies backed by private credit has thrust a fast-growing and opaque corner of Wall Street lending into the spotlight.Private credit, also known as direct lending, is a catch-all term for lending done by nonbank institutions. The practice has been around for decades but surged in popularity after post-2008 financial crisis regulations discouraged banks from serving riskier borrowers. That growth — from $3.4 trillion in 2025 to an estimated...