Mr. Trump made his latest comments on North Korea during a pair of televised media events that covered a dizzying array of topics. He assailed Senator Mitch McConnell, the Republican leader, for not passing his legislative priorities, calling it “disgraceful” that the party’s health care plan failed by one vote and hinting that the leader should step down if he cannot do better. Mr. Trump also said he would declare the opioid epidemic a national emergency and defended his decision to bar transgender people from the armed forces, saying he was “doing the military a great favor.”
In his first response to Russia’s decision to force the United States to slash its diplomatic staff in half, the president said he would thank President Vladimir V. Putin for helping him trim payroll costs. Mr. Trump expressed sympathy for his former campaign chairman, Paul J. Manafort, whose house was raided last month by law enforcement agents as part of an investigation into Russia ties, calling him “a very decent man.” He said he was not considering firing Robert S. Mueller III, the special counsel.
After nearly a week of his working vacation here, the president was in an expansive mood and seemingly eager to talk and take on all issues. While his press secretary Sarah Huckabee Sanders, held a sign in the back of the room saying “one more question,” Mr. Trump kept plowing ahead, taking one after another until he was satisfied.
Joining him at the club were Vice President Mike Pence and several aides, including Lt. Gen. H. R. McMaster, his national security adviser, who has been under fire from the alt-right media after purging his staff of several hard-liners thought to be close to Stephen K. Bannon, the president’s chief strategist. Mr. Trump said he “absolutely” had confidence in General McMaster.
Mr. Trump’s rhetoric on North Korea has reached a level that has alarmed allies in Asia and many Americans at home. Investors were unnerved on Thursday by the increasing tension. The Standard & Poor’s 500 stock index fell by 1.45 percent as investors sold out of highflying stocks such as Amazon, Facebook and Netflix. It was the sharpest daily decline in the benchmark S.&P. 500 since May 17.
Democrats complained that the president was inflaming the confrontation and called for diplomacy instead. “President Trump’s escalatory rhetoric is exactly the wrong response to dealing with North Korea’s provocative behavior,” said Senator Ed Markey of Massachusetts, the top Democrat on the Foreign Relations Committee’s East Asia Subcommittee. “It unnecessarily heightens the risk of miscalculation and creates the very fog that can lead to war.”
More than 60 House Democrats sent a letter on Thursday to Secretary of State Rex W. Tillerson asking him to restrain the president. “These statements are irresponsible and dangerous, and also senselessly provide a boon to domestic North Korean propaganda, which has long sought to portray the United States as a threat to their people,” the letter said.
Former President Jimmy Carter, who has visited North Korea three times as a private citizen, added his voice to the criticism. “In addition to restraining the warlike rhetoric, our leaders need to encourage talks between North Korea and other countries, especially China and Russia,” he said in a statement. He added that all parties must assure the North Koreans that they would forgo “any military action against them if North Korea remains peaceful.”
For all the bellicose words, Mr. Trump said on Thursday that he was open to negotiations, as Mr. Tillerson has urged. But the president expressed skepticism that talks would lead to a reasonable outcome, given the experiences of his predecessors Bill Clinton, George W. Bush and Barack Obama, none of whom was able to resolve the issue through negotiations.
“Sure, we’ll always consider negotiations,” Mr. Trump said. “But they’ve been negotiating now for 25 years. Look at Clinton. He folded on the negotiations. He was weak and ineffective. You look what happened with Bush, you look what happened with Obama. Obama, he didn’t even want to talk about it. But I talk. It’s about time. Somebody has to do it.”
Mr. Trump likewise said he doubted that sanctions passed unanimously by the United Nations Security Council last weekend would ultimately succeed. But he again suggested that he would bargain with China by backing down from a planned trade war if Beijing did more to resolve the North Korea impasse.
“We lose hundreds of billions of dollars a year on trade with China,” he said. “They know how I feel. It’s not going to continue like that. But if China helps us, I feel a lot differently toward trade, a lot differently toward trade.”
He was vague about exactly where the line would be if North Korea did not back down, and refused to say whether he would consider a pre-emptive military strike without an attack by Pyongyang.
Asked what would be “tougher” than “fire and fury,” he demurred. “Well, you’ll see, you’ll see.”
Stress within the administration over North Korea again spilled over and into public view on Thursday. Speaking with reporters en route to Seattle, Defense Secretary Jim Mattis said the president was entitled to use whatever language he thought appropriate. “I was not elected,” he said. “The American people elected the president.”
But asked about his own equally tough but less colorful statement about North Korea, issued on Wednesday, Mr. Mattis said, “The rhetoric is up to the president. This is my rhetoric.”
A White House aide, meanwhile, said no one should listen to Mr. Tillerson on military matters related to North Korea after the secretary of state said he saw no imminent likelihood of war and urged Americans to sleep soundly.
“The idea that Secretary Tillerson is going to discuss military matters is simply nonsensical,” Sebastian Gorka, a deputy assistant to the president, told BBC Radio. “It is the job of Secretary Mattis, the secretary of defense, to talk about the military options.”
That drew a sharp retort from Mr. Tillerson’s spokeswoman. “He’s a cabinet secretary,” Heather Nauert, the State Department spokeswoman, told reporters. “He’s fourth in line to the presidency. He carries a big stick.”
Mr. Gorka went on Fox News to say his comment was misunderstood. “I was admonishing the journalists of the fake news industrial complex who are forcing our chief diplomat into a position where they are demanding he makes the military case for action when that is not the mandate of the secretary of state,” he said.