“You only find out who is swimming naked when the tide goes out,” Warren Buffett warned almost a decade ago. Lots of swimmers who have been happily paddling along in the nude are starting to feel a chill as signs mount that the interest-rate tide is indeed starting to expose their condition. Let’s call them the debtor class: according to the McKinsey Global Institute, total global debt—sovereign, corporate, and household—has increased by 74 percent since the 2008 financial crisis.

Start with the many emerging economies that have taken on staggering amounts of debt. And not any old sort of debt, but debt denominated in U.S. dollars. They must buy dollars with which to pay interest and principal on their IOUs. And because the American economy is booming and the Federal Reserve Board’s policy makers are steadily raising interest rates, making dollar investments more attractive and strengthening the American currency, investors are pulling funds from emerging economies and moving them to America.