After weeks of bluster and escalation, President Trump blinked. Then he blinked again. And again.

He backed off his threat to fire the Federal Reserve chairman. His Treasury secretary, acutely aware that the S&P 500 was down 10 percent since Mr. Trump was inaugurated, signaled he was looking for an offramp to avoid an intensifying trade war with China.

And now Mr. Trump has acknowledged that the 145 percent tariffs on Chinese goods that he announced just two weeks ago are not sustainable. He was prompted in part by the warnings of senior executives from Target and Walmart and other large American retailers that consumers would see price surges and empty shelves for some imported goods within a few weeks.

Mr. Trump’s encounter with reality amounted to a vivid case study in the political and economic costs of striking the hardest of hard lines. He entered this trade war imagining a simpler era in which imposing punishing tariffs would force companies around the world to build factories in the United States.

He ends the month discovering that the world of modern supply chains is far more complex than he bargained for, and that it is far from clear his “beautiful” tariffs will have the effects he predicted.

This is not, of course, the explanation of the events of the past few days that the White House is putting out. Mr. Trump’s aides insist that his maximalist demands have been an act of strategic brilliance, forcing 90 countries to line up to deal with the president. It may take months, they acknowledge, to see the concessions that will result. But bending the global trade system to American will, they say, takes time.

“Have some patience and you will see,” the president’s press secretary, Karoline Leavitt, told reporters on Wednesday.