Just hours from now, at midnight, President Trump is set to impose steep new tariffs on many of America’s biggest trading partners. The fee on imports from China, for example, will rise from 30 percent to at least 104 percent. America’s top trade official defended the levies today as “a moment of drastic, overdue change.”

At least 70 governments have already approached the U.S. to discuss rolling back the tariffs, and the administration signaled today that it was ready to negotiate. But the president and his advisers have been clear that the appeals will not stop the tariffs from going into effect.

China has vowed to “fight to the end”; other countries, like Japan, indicated a willingness to compromise; the E.U. is trying to do a bit of both. Billionaire investors, worried that the tariffs will drag down the economy, have been calling the White House to push Trump to reverse course — though it’s not clear that they’ve had any effect.

That uncertainty has translated into massive volatility in the stock market. This morning, the S&P 500 was up 4 percent; it finished down about 1.6 percent. The early rally, seemed “to be pinned, in part, on the prospects for deals to lower tariffs,” Jason Karaian, our deputy business editor, said. That optimism may have faded.

A coal facility outside Welch, W.Va., last month.Credit…Evelyn Hockstein/Reuters

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