Wall Street’s slide resumed on Thursday, another anxiety-induced drop that left the S&P 500 brushing up against a “correction” — a symbolic marker of the speed at which investors have fled the stock market in recent weeks.

Traders, economists and business leaders have been grappling with a rapidly shifting economic landscape as President Trump has imposed and threatened new tariffs on imports that could upend global trade and undermine complex supply chains for big companies.

On Thursday, Mr. Trump threatened to impose 200 percent tariffs on European wine and champagne, one day after the European Union announced retaliatory tariffs on imports of U.S. whiskey and several other American products. The president has already added tariffs on steel and aluminum imports, and a wide swath of products from China.

The S&P 500 fell more than 1 percent on Thursday, a drop that briefly left it about 10 percent below its Feb. 19 peak. A drop of more than 10 percent is called a correction, which on Wall Street serves as a signal that investors have turned pointedly more pessimistic about the market.

The constantly moving goal posts have left investors so rattled that even recent good news about the economy hasn’t had a calming effect. On Thursday a report on weekly unemployment claims came in lower than expected. On Wednesday a better-than-expected reading of the Consumer Price Index had briefly helped bolster stocks.

Investors are worried that tariffs, once in full effect, will push prices higher — hurting business and consumers. Mr. Trump’s immigration policies and firings of federal employees through the so-called Department of Government Efficiency are also looming in the backdrop.

“The outlook for inflation depends more on tariffs, deportations and DOGE than the backward-looking data releases right now,” Bill Adams, chief economist for Comerica Bank, said on Thursday.