Mr. Xi opened the dialogue with a speech that stressed the positive, saying China and the United States had more common interests than differences. He also emphasized China’s economic and military strength. “The vast Pacific Ocean has ample space to accommodate two great nations,” he said, suggesting as he has previously that China would play a much bigger role in the Pacific.

The best prospect seems to be the effort toward a bilateral investment treaty that China agreed to start negotiations on last year.

Toward that end, China’s vice minister of finance, Zhu Guangyao, said Monday that talks would begin soon on lifting restrictions on foreign investments in both countries, such as cutting back on the national security reviews Washington conducts before approving big Chinese investments in the United States.

In one critical area — cyberespionage — there is unlikely to be any real discussion. After the Justice Department won the indictments of five members of the Chinese People’s Liberation Army on charges of cybertheft in May, China suspended a working group that had held only two sessions.

The atmosphere between Beijing and Washington has deteriorated to such an extent since Mr. Xi and President Obama met at the Sunnylands estate in California a year ago that even pressuring a nuclear North Korea, the one area they agreed to pursue at that time, has almost vanished from the agenda, American officials said.