“There’s no doubt that the equity market does not like higher rates — there’s just no debate about it,” Ralph Axel, director of U.S. Rates Strategy at Bank of America.

Lauren Goodwin, an economist at New York Life Investments, wrote in a note to clients that investors have begun seeking out safer investments while weighing concerns including the debt-ceiling fight and regulatory actions in China.

The Chinese government has shown signs of sharply shifting away from the policies that have guided its economy for much of the last decade, tightening regulation on subjects like online gaming and data sharing by tech companies. And Beijing has so far been reluctant to bail out the teetering Evergrande Group, a beleaguered residential developer with $300 billion in debt, another shift from typical policy.

But, Ms. Goodwin wrote, risks like that “should do little to impact the broader fundamental environment.” Instead, she said, the forces driving the market in the near future would remain those that have done so throughout the past 18 months: the spread of the virus, government spending, and decisions by the Federal Reserve.

“The path will depend heavily on our three highly uncertain drivers — the pandemic, monetary policy and fiscal policy,” she wrote.

While the slowdown of bond-buying will start sooner rather than later, the Fed’s main policy interest rate — its more powerful and traditional tool — remains near zero. And the Fed chair, Jerome H. Powell, and his colleagues have signaled that the central bank is a long way from raising interest rates because it wants to see the job market return to full strength before doing so.

“The test for raising interest rates is substantially higher,” Mr. Powell said at a Senate Banking Committee hearing on Tuesday. What the Fed wants to see, he said, is a “very strong” labor market: “The kind of thing that we did see before the pandemic arrived.”

Jeanna Smialek and Matt Phillips contributed reporting.