Asked if he would resign if Mr. Trump asked him to do so, Mr. Powell replied directly: “No.”

Mr. Powell was joined onstage at the annual meeting of the American Economic Association by his immediate predecessors at the Fed, Janet L. Yellen and Ben S. Bernanke. Both of them criticized Mr. Trump’s attacks as potentially damaging to the central bank, and therefore to the economy.

Strong economic growth fueled the Fed’s decision to raise its benchmark rate four times in 2018, into a range from 2.25 percent to 2.5 percent. The rate, which had hovered near zero in the wake of the financial crisis a decade earlier, now sits at the lower end of the range that Fed officials consider a reasonable estimate of “neutrality,” meaning that the central bank is neither encouraging nor discouraging economic growth.



Fed officials say the continued strength of the economy validates their management of monetary policy. “I think we’re actually in a good spot,” Loretta Mester, president of the Federal Reserve Bank of Cleveland, told CNBC on Friday, noting that job growth is strong and inflation is under control.

But critics, including Mr. Trump, have said the economy still needs the Fed’s help. Inflation remains below the 2 percent annual pace the Fed regards as optimal, suggesting that the economy has room to grow, and workers are only beginning to reap the benefits of an expansion now in its 10th year.

Clouds also are gathering on the economic horizon. The Trump administration increased economic growth last year through large tax cuts and increased federal spending, but those benefits are waning. And Mr. Trump’s trade war with China is beginning to be felt by American companies, like Apple and FedEx, which have warned that the tit-for-tat tariffs are pinching profits.



The Fed’s decision to raise the benchmark rate at its most recent meeting, in mid-December, drove down stock prices and bond yields in a show of concern about the prospects for continued economic growth. Asset prices imply an expectation that the Fed will not raise interest rates at all during 2019.



Mr. Powell began his remarks by reiterating his view that the markets’ concerns are overstated. He said that 2018 had been “a good year for the United States economy” and that the latest economic data suggested “ongoing momentum heading into 2019.” Wall Street’s pessimism, he said, is “well ahead of the data.”