Trump’s sweeping tariff regime roiled markets, driving the S&P 500 to the brink of a bear market and sending yields on long-term US bonds soaring. Wall Street titans, including many who’d backed Trump, reacted with alarm. Ken Griffin called the tariffs a “huge policy mistake.” Bill Ackman warned of “economic nuclear war.” Jamie Dimon grimly predicted a recession as the “likely outcome.” The scale and suddenness of Trump’s attack on US trading partners only magnified its impact—including the panic that ensued. No one had quite grasped what was coming. It cut against what investors thought they knew about Trump: that he should be taken “seriously, not literally”; that although he was disruptive and unpredictable, he ultimately longed for a booming stock market and the imprimatur of success he believed it conferred on him. And so, the thinking went, he’d never do anything to truly jeopardize that.