Last week the financial system ran out of cash. It was a modern version of a bank run, and it’s not over yet. Stepping back, it reveals two big things about financial markets: first, US Treasuries are not truly “risk-free” assets, as most consider them to be, and second, big banks are significantly undercapitalized. The event doesn’t mean another financial meltdown is necessarily imminent—just that the risk of one is heightened—since the brush fire can be doused either by the Fed, or by the banks raising more equity capital. However, it provides a “teachable moment” regarding systemic fragility and anti-fragility. Here’s a plain-English explanation of what’s happening, and what it means for bitcoin. Enjoy!