Stocks turned lower Wednesday after a disappointing Treasury bond auction accelerated a selloff in the debt market. The Dow Jones Industrial Average dropped about 600 points, or 1.5%, leading indexes lower in afternoon trading.

President Donald Trump ended the week on a grumpy note, rattling his tariff saber — and stock-market investors — on Friday as he threatened levies on Apple Inc. and the European Union. But for all the renewed trade drama, it was moves in the bond market that have been the center of attention.

Financial markets are once again focused on Washington, D.C., but taxes, not tariffs, are driving recent price action.