On Tuesday, at his daily briefing, Mr. Trump was candid about the transactional rationale behind his stance toward China. Pressed on how he could criticize the World Health Organization for what he called pushing “China’s misinformation,” after he had also lavished praise on Beijing’s purported transparency, he responded, “Well, I did a trade deal with China, where China is supposed to be spending $250 billion in our country.”

“I’d love to have a good relationship with China,” he added.

On Friday, however, he posited that China must have the most deaths from the coronavirus — the United States does — and later said, “I’m not happy with China.” He repeated the assertion on Saturday, saying that China had many more deaths than it had reported, and that the virus “could have been stopped in China. Before it started.’’ But he continued to show deference to Mr. Xi, saying “I don’t want to embarrass countries that I like and leaders that I like, but you have to see some of these numbers.”

Despite the president’s diverging public statements, a central pillar of his campaign’s approach is to deflect anger over the human casualties and economic pain of the coronavirus onto an adversary that many Americans already view warily.

The strategy includes efforts to leverage the U.S.-China relationship against Mr. Biden, who Republicans believe is vulnerable because of his comments last year playing down the geopolitical challenge posed by China and what Republicans claim was high-paying work that his son, Hunter, has done there. (A lawyer for the younger Mr. Biden said he was uncompensated for his work.)

Mr. Biden, for his part, has criticized Mr. Trump’s warm words for China. On Friday, his campaign released a video assailing the president for not pressing Mr. Xi to let the Centers for Disease Control and Prevention into his country and for being “more worried about protecting his trade deal with China than he was about the virus.”



On a conference call with reporters, Antony J. Blinken, a senior Biden adviser, noted that in January and February “the president praised China and President Xi more than 15 times.” He attributed the flattery to the administration’s not wanting to “risk that China pull back on implementing” the initial trade agreement the two countries signed in January.