“On the U.S. side, the tradition has been steely resolve and preparation,” said Dennis C. Blair, a retired admiral and head of the United States Pacific Command who went on to serve as director of national intelligence. “But now we have a president who reacts to braggadocio with an attempt to top it on his own side. He’s out there in territory he thinks is familiar, which is meeting exaggerated statement with exaggerated statement, convincing the other side that we’re tough, you’re going to fold.”
In other words, the magnitude of the challenges that Mr. Trump faces has grown dramatically, but his tone has not. And it remains to be seen if the don’t-mess-with-me attitude that cowed Republican primary rivals like Jeb Bush will have a similar effect on a regime that has managed to develop an intercontinental ballistic missile that could reach the United States while making progress toward miniaturizing a nuclear warhead that would fit on top.
In this case, Mr. Trump has told people around him that he thinks Kim Jong-un, the unpredictable North Korean leader, will ultimately be prodded to cut a deal, and that the bluntness of his language is intended to create a crisis that drives him to negotiate before North Korea perfects a nuclear-tipped missile capable of striking the American mainland.
Unlike other presidents, who rejected direct contact with their North Korean counterparts, Mr. Trump has even suggested that he would meet with Mr. Kim if the circumstances were right, perhaps for a hamburger.
“If Kim were to respond positively, Trump might end up as his best friend,” said Scott Snyder, director of the program on United States-Korea policy at the Council on Foreign Relations. “I think it is as plausible that we could end up with a ‘hamburger summit’ between Trump and Kim as that we will end up in a second Korean War.”
While Mr. Trump and his staff say his statements reflect a desire to deal with the North Korea problem once and for all, they also have an unmistakable domestic political component, according to people in the president’s orbit. He feels besieged by the investigation into his campaign’s possible collusion with Russia and frustrated by his sinking poll numbers, and he is seeking targets to attack. Asserting his strength abroad in such stark terms when he is so weak at home helps him politically and, more important, improves his wavering state of mind, according to current and former advisers. The tough talk also seems to appeal to many of his most ardent supporters.
As for the effect on North Korea, Mr. Blair said the dictatorship has stood down from confrontations when convinced that the United States was serious. “It’s probably good to throw back at them what they throw at us,” he said. “When they think we’re angry, they back off.”
To much of the foreign policy establishment in both parties, however, the approach is alarming. “When I was watching the president talk, I thought, ‘Oh, my god, why is he doing this?’” said Senator Dianne Feinstein, Democrat of California and the former chairwoman of the Senate Intelligence Committee. “Anybody who knows anything about this young Korean leader knows it’s going to promote an even more aggressive response.”
“I just wished he’d stop it, with the tweeting one day and the next day, it’s something else,” Mrs. Feinstein added. “Why isn’t the secretary of state the one making the statements? Why didn’t he at least make it at the White House and not some golf course, or wherever he was? He speaks for the whole country, not just for his feelings at the moment. It’s just dangerous.”
Mr. Trump’s statements have been as vague as they have been vivid, not clearly defining what his red line would be. What would prompt an American strike? When Mr. Trump made his fire-and-fury comment on Tuesday, he said it would come in reaction to a threat to the United States, not necessarily an attack. In subsequent comments, he has said he would react if North Korea launched a strike against American interests, like the Pacific territory of Guam, or United States allies in the region.
Similarly, what would he require as the goal of any negotiations? Would North Korea have to freeze its nuclear program or give it up altogether? Could he live with a deal that merely puts off the problem, like the Iran nuclear agreement brokered by his predecessor that he routinely excoriates? Mr. Trump said in recent days that he wanted to “denuke the world,” but many doubt North Korea would ever surrender its weapons now that it has developed them.
Some of Mr. Trump’s advisers, including Stephen K. Bannon, his chief strategist, have urged him to take a less interventionist stance, but Mr. Bannon has been kept out of most of the deliberations. Mr. Mattis, for his part, has advised Mr. Trump to project strength and resolve. But he has quietly lamented to lawmakers from both parties the absence of military options against North Korea that would not imperil the lives of millions of civilians in South Korea and Japan.
And Secretary of State Rex W. Tillerson, who flew to New Jersey to meet with Mr. Trump after consulting with leaders in Asia over the past week, has complained privately about the lack of coordination between the White House and his department, which has often been blindsided by the president’s statements.
Even some of the president’s own advisers have quietly asked each other in recent days if Mr. Trump’s bellicosity toward North Korea is part of some thought-out strategy that they have not been told about or what they suspect is just more on-the-fly instinct. But some aides have found themselves surprised at other moments when Mr. Trump has done something unexpected and seemingly random, only to explain his thinking afterward in a way that indicated more calculation than they had thought.
Aides do know that after a lifetime in the real estate business, Mr. Trump starts a negotiation with an extreme position intended to ensure that the other side meets him not just in the middle but closer to his side. While he has little experience in translating that into international diplomacy, Mr. Trump has shown that he is not so wedded to any particular position on almost any issue, meaning he might be more likely to accept a compromise that would seem unthinkable judging by the stark language he uses at the start.
Mr. Snyder of the Council on Foreign Relations said that Mr. Trump could be North Korea’s greatest nightmare and its greatest opportunity. He might be a nightmare, Mr. Snyder said, because he would not be constrained by norms that would favor acquiescence over military force. And he might be an opportunity because, Mr. Snyder said, “the chances of Kim being able to cut a deal with an unconventional Trump are higher than they would be with a president more sensitive to the politics of nuclear diplomacy with North Korea.”
Still, many former diplomats remain deeply skeptical. Ivo H. Daalder, a former ambassador to NATO who is now the president of the Chicago Council on Global Affairs, said the likelihood of forging a workable agreement with North Korea was so slim that it suggested Mr. Trump’s language of the past week was meant more for domestic audiences and to show his base that he was tough.
“If their bottom line is denuclearization or even eliminating a nuclear capability that can reach the U.S., that strikes me as unrealistic,” Mr. Daalder said. “Pyongyang has gone through great effort to acquire this capability, which its leaders judge necessary to ensure their survival. They’re not about to give it up. So that leaves me to think that strong rhetoric is its own purpose.”