SEOUL — The mystique of Shangri-la as a make-believe land of peace and harmony did not exactly pervade the atmosphere between the American and Communist Chinese defense chiefs in what’s known as the “Shangri-la dialogue” at Singapore.

The American defense secretary, Lloyd Austin, on Saturday accused the Chinese of “provocative and destabilizing military activity near Taiwan,” the Free Chinese island state that’s acknowledged as a province of mainland China. Such activity, he said, threatens the “security, and stability and prosperity in the Indo-Pacific,” while Washington prefers to focus on “peace, stability and the status quo across the Taiwan Strait.”

Beijing’s defense minister, General Wei Fenghe, on Sunday accused Washington of attempting to “impose its will on others” and “bully others” in a campaign “to hijack countries in our region and target one specific country.”

The best that could be said about the exchange was that Mr. Austin and General Wei met one another, shook hands, and dined on opposite sides of the table at an elaborate luncheon for top-ranked defense ministers at Singapore’s Shangri-la Hotel, from which the dialogue gets its name.

It was the first such dialogue in two years, and ministers and top officials from nearly 40 countries mixed and mingled, engaging in the kind of tête-a-tête that would otherwise be almost impossible. On the overwhelming question of China’s pursuit of regional hegemony, however, there clearly was not much scope for any agreement between Washington and Beijing — or even agreeing to disagree.

General Wei qualified his rhetoric, however, by giving the impression that China would not go to war over Taiwan as long as Taiwan showed no signs of declaring itself an independent country. 

Taiwan’s formal name has remained the “Republic of China” ever since the “nationalist” forces of Chiang Kai-shek fled to the island redoubt 100 miles across the Taiwan Straits from the mainland as Mao Zedong’s Red Army was storming to victory in 1949. Washington recognized Beijing as the capital of “one China” in 1978.

In a burst of bluster, General Wei vowed his forces would “resolutely smash any schemes for Taiwan independence if anyone dares to split off Taiwan.” The Red army, he declared, “will not flinch from the cost and will fight to the very end.”

Although the temperature level has definitely increased of late, Mr. Austin the day before had sought to reassure the Chinese that “our policy has not changed” and that Washington recognized “one China,” just as President Biden stated last month during his summit in Tokyo with Japan’s prime minister, Fumio Kishida. 

Mr. Biden, however, upset Beijing when he said Washington would stick by its “commitment” to defend Taiwan, which has been importing large amounts of American arms in case China finally invades across the straits.

Washington has no troops, nor even advisers, on Taiwan and maintains relations through an “American Institute” that replaced the former embassy, but Taiwan is an important customer of American arms. Most recently Washington has agreed to sell $120 million for the upkeep of the Taiwan navy, which would be vital in case of attack from the mainland.

General Wei addressed the contentious issue of American military support for Taiwan, if only in arms, not troops. Equating arms sales with “interfering in China’s internal affairs,” he said Washington should not try to use the island fortress in order to “control China.”

General Wei’s meeting with Japan’s defense minister, Nobuo Kishi, was by comparison quite low key even though Japan is just as anxious as Washington to maintain Taiwan in its present status as separate from the mainland, both geographically and administratively.

Mr. Kishi in his meeting with General Wei began by saying there were “many concerns including various security issues, between Japan and China,” according to Nihon Keizai Shimbun, the Japanese financial newspaper. General Wei responded most diplomatically that “we want to develop relations based on trust and the consensus of both governments while strengthening cooperative relations through dialogue.”

There was no doubt, though, of concerns about diplomacy winding up in war. One of the most significant meetings during the dialogue was a session away from the conference table among Messrs. Austin and Kishi and South Korea’s defense minister, Lee Jong-sup.

South Korea’s defense ministry said they agreed “to step up cooperation to counter North Korea’s missile threat through their combined regular security exercises, including missile warning drills,” according to Yonhap, the South Korean news agency.

Leaders of all three countries have been pressing for full cooperation in view of North Korean missile tests and the strong possibility that North Korea’s leader, Kim Jong-un, will order another underground nuclear test.

The consensus among them is that heightened cooperation will be the next best thing to a trilateral alliance, which all sides see as impossible. Japan and South Korea both have separate alliances with the United States, but mutual animosity dates from the era of Japanese colonial rule over South Korea that ended with the Japanese surrender at the end of World War II in 1945.

The defense chiefs were reported as having “agreed to conduct the South Korea-U.S.-Japan missile warning and ballistic missile search and tracking exercises.” While they’ve been quietly conducting these exercises for the past four years, a source was quoted as saying they will now do so “more publicly.”

North Korea’s defense minister did not attend the conference. As a reminder of North Korea’s military potential, the South’s joint chiefs of staff in Seoul said North Korea on Sunday fired several artillery shots, possibly missiles. 

And just to remind all those at the conference of the origin of the name Shangri-la, the book “Lost Horizon,” written by the British author James Hilton in the 1930s, was on bedside tables. The book is about an idyllic fictional valley named Shangri-la in Tibet.