WASHINGTON — As he tries to tackle the greatest challenges to American power in Asia, President Trump is overturning policy toward China and North Korea that for decades was as canonical as Confucian ritual.
With North Korea, he is engaging with the enemy in hopes that negotiations will yield a surrender of nuclear weapons. With China, Mr. Trump says the United States must take a big step back from an economic relationship that has strengthened a formidable rival.
The shifts were prompted by internal changes in each country, combined with Mr. Trump’s unorthodox instincts and the views of his senior Asia advisers. The administration now has growing bipartisan support in Washington to widen an emerging global conflict with China and build diplomacy with North Korea.
This week, American negotiators are pressing forward with the policy transformations.
Treasury Secretary Steven T. Mnuchin and Robert E. Lighthizer, the United States trade representative, spoke to Chinese counterparts on Tuesday by telephone to continue tough trade negotiations. Meanwhile, Stephen E. Biegun, the special representative for North Korea, was in Brussels and Berlin to discuss diplomatic approaches to North Korea.
The meetings follow Mr. Trump’s June trip to East Asia, where he met separately with President Xi Jinping of China and Kim Jong-un of North Korea.
“The administration has changed the nature of U.S. government interaction in many ways with both North Korea and China,” said James Green, the former senior trade official in the United States Embassy in Beijing. “In both cases the traditional mechanics of diplomacy have been upended.”
More important, Mr. Trump has smashed the very foundations of longstanding policy.
That has alarmed some experts. More than 150 former officials and scholars signed an open letter that the writers posted last week, denouncing the administration’s combative China policy as “fundamentally counterproductive.”
“We do not believe Beijing is an economic enemy or an existential national security threat that must be confronted in every sphere,” said the letter, which was organized by scholar Michael D. Swaine.
Yet the aggressive approach to China has drawn many supporters, including some Obama administration officials and Democratic leaders like Senator Chuck Schumer. “Hang tough on China, @realDonaldTrump. Don’t back down,” Mr. Schumer tweeted in May. “Strength is the only way to win with China.”
Since the 1970s, when presidents Richard Nixon and Jimmy Carter re-established relations with Beijing, American officials and experts have contended that economic ties between the United States and China would anchor the relationship between the two nations and, perhaps, coax Communist Party leaders toward Western liberalism.
But Mr. Xi, who took power in 2012, has exercised expansive authoritarian controls. He has detained more than one million Muslims in camps, reinforced the party’s role across strategic industries and expanded the military’s footprint in disputed areas of the South China Sea.
One economist who advised Chinese leaders in the 1980s, Janos Korani, wrote this week that Western experts like himself had been Dr. Frankensteins, helping build up China without realizing the eventual consequences for the West. “Now, the fearsome monster is here,” he wrote.
Trump administration officials argue that economic engagement without appropriate guardrails created a tyrannical behemoth that could supplant American supremacy. Some call for long-term tariffs to “decouple” the economies of China and the United States by breaking supply chains and other business ties.
“We seem to be at a unique confluence of Xi and Trump,” said Bill Bishop, an analyst in Washington who publishes Sinocism, a China briefing. “And Make China Great Again meets Make American Great Again is a recipe for friction.”
But Mr. Trump rarely if ever talks about strategic concerns and speaks admiringly of Mr. Xi, leading China hawks to fear a trade deal with Beijing that relents on national security issues like Huawei.
On North Korea, the general policy since the George W. Bush administration has been to avoid bilateral diplomacy and impose economic isolation to force Pyongyang to end its nuclear program.
But Mr. Trump upended that by doing face-to-face diplomacy with Mr. Kim, most recently when the two strolled for a minute in North Korea — the first time a sitting American president had entered the country. It was their third meeting, after a failed Hanoi summit in February and initial talks in Singapore in June 2018.
Former officials and analysts increasingly say diplomacy is the only way forward with North Korea, given that it already has an estimated 30 to 60 nuclear warheads. Longtime advocates of rapprochement point optimistically to the shifting consensus in Washington.
“My impression is that they are certainly singing in a new key, and it’s a good thing however or why ever they are doing so,” said Robert L. Carlin, a former North Korea analyst at the C.I.A. and State Department.
He added that if the foreign policy establishment was “reconsidering the situation, what’s possible, what’s pragmatic and realistic after nearly two decades of feckless policy, that’s all to the good, and maybe just in time. “
A notable figure now preaching diplomacy is Michael Morell, the former acting C.I.A. director and host of the “Intelligence Matters” podcast.
“A negotiated solution is the only solution to this problem,” he said on CBS News’s “Face the Nation” on June 30. “There isn’t a military option. There’s not a covert action option. So getting back to talks with the North Koreans is important, and I think that’s a good thing.”
He also said the United States would have to live with a nuclear North Korea because Mr. Kim would not give up his nuclear weapons program — an assessment reached by the intelligence community. “We should push for the whole thing, but the best we can hope for is limits,” he said.
“Containment?” asked Margaret Brennan, the host.
“Containment,” Mr. Morell agreed.
In a telephone interview, Mr. Morell said the administration’s ability to shift consensus thinking is only possible because of Mr. Trump “being the Republican president that he is.”
“So political Washington in its entirety has come around to the opinion that talking to North Korea is good,” he said.
Trump administration officials stress that the goal of negotiations is to get Mr. Kim to give up all of his nuclear weapons. But senior State Department officials are now contemplating intermediate steps — including reaching a freeze of nuclear activity — rather than going for a grand deal, as Mr. Trump tried to do in Hanoi.
Morgan Ortagus, the State Department spokeswoman, said Tuesday that a freeze would be the “beginning of the process.”
Mr. Trump could shift the consensus further, if he decides the United States can tacitly accept a nuclear North Korea. Beyond Mr. Morell, other analysts are coming to that conclusion — one that would have drawn outrage if mentioned aloud during the Obama administration.
“I can’t see Kim giving up his nuclear weapons entirely,” said Jean H. Lee, a Korea expert at the Wilson Center in Washington. “They are his ‘treasured sword’ and all that he has to give him leverage. But he is willing to barter some dismantling of his nuclear program in exchange for concessions.”
Under former President Barack Obama, the United States reached a nuclear freeze deal with North Korea in 2012 but quickly backed out when Pyongyang announced a satellite launch.
Obama officials stuck to a strategy of pressuring North Korea through sanctions, which the Trump administration is also doing. But Mr. Obama did not try face-to-face diplomacy with Mr. Kim — something that one senior Obama official, Daniel Russel, called “diplotainment” when done by Mr. Trump.
“It was something the North Koreans repeatedly requested,” said Mr. Russel, a former assistant secretary of state for East Asian and Pacific affairs.
He said Obama officials considered it, “but immediately recognized that it would be worse than foolish to legitimize Kim with a summit before the groundwork had been laid for a denuclearization deal.”