BEIJING — With President Xi Jinping safely out of the United States and no longer President Trump’s guest, China’s state-run media on Saturday was free to denounce the missile strike on Syria, which the American president told Mr. Xi about while they were finishing dinner.

Xinhua, the state news agency, on Saturday called the strike the act of a weakened politician who needed to flex his muscles. In an analysis, Xinhua also said Mr. Trump had ordered the strike to distance himself from Syria’s backers in Moscow, to overcome accusations that he was “pro-Russia.”

That unflattering assessment reflected China’s official opposition to military interventions in the affairs of other countries. But it was also a criticism of Mr. Trump himself, who Mr. Xi had hoped was a man China could deal with.

Chinese officials had feared that the two leaders’ 24-hour encounter at Mr. Trump’s Mar-a-Lago estate in Florida might be marred by a campaign-style anti-China outburst from Mr. Trump. Instead, it was interrupted by the unexpected missile attack.

Some Chinese analysts viewed the strike’s timing as no coincidence. Mr. Trump wants China to do more to deter the development of nuclear weapons by North Korea, its ally, and these analysts viewed the Syria attack as a reminder to Mr. Xi that the United States could also attack the North, if necessary.

The missile strike on Syria overshadowed meetings that American and Chinese officials described as big-picture conversations on trade as well as North Korea, which stopped short of producing specific agreements.

Both sides agreed that the North Korean threat had reached a “very serious” stage, according to Secretary of State Rex W. Tillerson. He said the United States was prepared to take its “own course” if China did not do more to rein in the North.

But the official Chinese account of the talks in Xinhua did not mention North Korea — a burning issue for Mr. Trump, but less so for Mr. Xi. Analysts said the omission was probably intentional, a response to the attack on Syria.

Xinhua’s commentary on the Syria strike also made no reference to North Korea. But it mentioned American missile attacks on Libya in 1986 and Sudan in 1998, and scolded the United States for not achieving its “political goals” in those instances.

“It has been a typical tactic of the U.S. to send a strong political message by attacking other countries using advanced warplanes and cruise missiles,” the article said.

The state-run media offered sanitized accounts of the Mar-a-Lago talks, emphasizing the sweeping green lawns on which the leaders walked and the ornate room where the official discussions took place. Those articles omitted the surprise of the Syria attack, in keeping with the goal of presenting an uplifting account of the two leaders meeting as peers.

Mr. Tillerson told reporters that when Mr. Trump notified Mr. Xi about the Syria strike toward the end of dinner, Mr. Xi expressed understanding, because it was punishment for a chemical attack that had killed children.

The Chinese president very rarely talks to the Chinese or foreign news media, making it almost impossible to determine his opinion about the attack or how he expressed it to Mr. Trump.

But Chinese analysts, whose advice is sometimes sought by the government on foreign policy questions, were scornful of the strike, which they viewed as a powerful country attacking a nation unable to fight back. And they rejected what they viewed as an unspoken American message equating Syria, which has no nuclear arsenal, with North Korea, which has carried out five nuclear arms tests and hopes to mount a nuclear warhead on an intercontinental missile.

“I don’t deny that the United States is capable of such an attack against North Korea, but you need to see that North Korea is capable of striking back,” said Lu Chao, director of the Border Studies Institute at the Liaoning Academy of Social Sciences. “That would create chaos.”

If Syria had nuclear weapons, the United States would not dare attack it, said Shen Dingli, a professor of international relations at Fudan University in Shanghai. “Chemical weapons and nuclear weapons are totally different,” Mr. Shen said. “A chemical bomb kills dozens of people, and the atomic bomb at Hiroshima killed hundreds of thousands.”

Mr. Shen added that many Chinese were “thrilled” by the attack because it would probably result in the United States becoming further mired in the Middle East.

“If the United States gets trapped in Syria, how can Trump make America great again? As a result, China will be able to achieve its peaceful rise,” Mr. Shen said, using a term Beijing employs to characterize its growing power. “Even though we say we oppose the bombing, deep in our hearts we are happy.”

On trade, Mr. Xi and Mr. Trump agreed to a “100-day plan” that Commerce Secretary Wilbur L. Ross said would include “way stations of accomplishment.” American business executives took that to mean there had been no deep negotiations on whether China would further open its markets to American companies.

Business leaders had expected the Chinese to announce investments in the United States that would create jobs, as a way to offset some of Mr. Trump’s complaints about the countries’ trade imbalance. But Mr. Xi made no such offers, at least publicly. According to an account in Xinhua, the Chinese invited the United States to participate in a program it calls One Belt One Road, an ambitious effort to build infrastructure projects across Asia to Europe, for which China hopes it can attract some American investment.

“The Chinese did not want to create the impression that Xi went to the U.S. to make concessions to Trump, that would come across as weakness,” said Yun Sun, a senior associate in the East Asia Program at the Stimson Center in Washington.

In the preparations for the talks, Chinese officials emphasized that they expected few concrete results because they viewed the Florida encounter as a getting-to-know-you session between two big personalities. In that sense, the Chinese prevailed, Ms. Yun said.

“It will be Trump who will have difficulty explaining to his voters what he got from the Chinese,” she said.