Two thousand years before the U.S. federal government’s debt crossed the $38 trillion threshold, the Roman Empire faced a similar-looking calculus: a state with increasingly expensive obligations and a very limited appetite for taxes. To pay for this discrepancy, emperors pursued a policy known as “debasement”: gradually shaving off the silver from the coins until the value of the metal became more about its symbol than the metal itself. In practical terms, it was a way to pay bills without fully admitti ...