President Donald Trump’s tariffs have spooked investors, with fears of an economic downturn driving a stock market sell-off that has wiped out $4 trillion from the S&P 500’s peak last month, when Wall Street was cheering much of Trump's agenda.

The U.S. stock market took a huge nosedive Monday after President Donald Trump refused to rule out a coming recession. The president’s tariffs have frightened investors with weeks of economic uncertainty—and Trump’s constant media blitzes have failed to provide much insight into his plans.