President-elect Donald J. Trump on Tuesday tempered some of his most extreme campaign promises, dropping his vow to jail Hillary Clinton, expressing doubt about the value of torturing terrorism suspects and pledging to have an open mind about climate change.

But in a wide-ranging hourlong interview with reporters and editors at The New York Times — which was scheduled, canceled and then reinstated after a dispute over the ground rules — Mr. Trump was unapologetic about flouting some of the traditional ethical and political conventions that have long shaped the American presidency.

He said he had no legal obligation to establish boundaries between his business empire and his White House, conceding that the Trump brand “is certainly a hotter brand than it was before.” Still, he said he would try to figure out a way to insulate himself from his businesses, which would be run by his children.

He defended Stephen K. Bannon, his chief strategist, against charges of racism, calling him a “decent guy.” And he mocked Republicans who had failed to support him in his unorthodox presidential campaign

In the midday meeting in the 16th-floor boardroom of The Times’s publisher, Arthur Sulzberger Jr., Mr. Trump seemed confident even as he said he was awed by his new job. “It is a very overwhelming job, but I’m not overwhelmed by it,” he said.

He displayed a jumble of impulses, many of them conflicting. He was magnanimous toward Mrs. Clinton, but boastful about his victory. He was open-minded about some of his positions, uncompromising about others.

The interview demonstrated the volatility in Mr. Trump’s positions.

He said he had no interest in pressing for Mrs. Clinton’s prosecution over her use of a private email server or for financial acts committed by the Clinton Foundation. “I don’t want to hurt the Clintons, I really don’t,” he said.

On the issue of torture, Mr. Trump suggested he had changed his mind about the value of waterboarding after talking with James N. Mattis, a retired Marine Corps general, who headed the United States Central Command.

“He said, ‘I’ve never found it to be useful,’” Mr. Trump said. He added that Mr. Mattis found more value in building trust and rewarding cooperation with terrorism suspects: “‘Give me a pack of cigarettes and a couple of beers, and I’ll do better.’”

“I was very impressed by that answer,” Mr. Trump said.

Torture, he said, is “not going to make the kind of a difference that a lot of people are thinking.”

Mr. Trump repeated that Mr. Mattis was being “seriously, seriously considered” to be secretary of defense. “I think it’s time, maybe, for a general,” he said.

On climate change, Mr. Trump refused to repeat his promise to abandon the international climate accord reached last year in Paris, saying, “I’m looking at it very closely.” Despite the recent appointment to his transition team of a fierce critic of the Paris accords, Mr. Trump said that “I have an open mind to it” and that clean air and “crystal clear water” were vitally important.

He held out assurances that he did not intend to embrace extremist positions in some areas. He vigorously denounced a white nationalist conference last weekend in Washington, where attendees gave the Nazi salute and criticized Jews.

Asked about his antagonism with the news media and his vow to toughen libel laws, Mr. Trump offered no specifics but told the group, “I think you’ll be happy.”

Despite his frequent attacks against what he has dubbed the “failing New York Times,” Mr. Trump seemed to go out of his way to praise the institution, which he called “a great, great American jewel, world jewel.” He did, however, say he believed The Times had been too tough on him during the campaign.

Pressed to respond to criticism in other areas, he was defiant. He declared that “the law’s totally on my side” when it comes to questions about conflict of interest and ethics laws. “The president can’t have a conflict of interest,” he said.

He said it would be extremely difficult to sell off his businesses because they are real estate holdings. He said that he would “like to do something” and create some kind of arrangement to separate his businesses from his work in government. He noted that he had turned over the management of his businesses to his children, which ethics lawyers say is not sufficient to prevent conflicts of interest.

He insisted that he could still invite business partners into the White House for grip-and-grin photographs. He said that critics were pressuring him to go beyond what he was willing to do, including distancing himself from his children while they run his businesses.

“If it were up to some people,” he said, “I would never, ever see my daughter Ivanka again.”

Mr. Trump did not dispute reports that he had used a meeting last week with Nigel Farage, the U.K. Independence Party leader, to raise his opposition to offshore wind farms. Mr. Trump has long complained that wind farms would mar the view from his golf course in Aberdeenshire, Scotland.

“I might have brought it up,” Mr. Trump said, then argued he had done so because of policy concerns about wind farms rather than any personal interest.

Mr. Trump rejected the idea that he was bound by federal antinepotism laws from installing his son-in-law, Jared Kushner, in a White House job. But he said he would want to avoid the appearance of a conflict and might instead seek to make Mr. Kushner a special envoy charged with brokering peace in the Middle East.

“The president of the United States is allowed to have whatever conflicts he or she wants, but I don’t want to do that,” Mr. Trump said. But he said that Mr. Kushner, who is an observant Jew, “could be very helpful” in reconciling the longstanding dispute between the Israelis and the Palestinians.

“I would love to be able to be the one that made peace with Israel and the Palestinians,” Mr. Trump said, adding that Mr. Kushner “would be very good at it” and that “he knows the region.”

“A lot of people tell me, really great people tell me, that it’s impossible — you can’t do it,” Mr. Trump added. “I disagree. I think you can make peace.”

“I have reason to believe I can do it,” he added.

Mr. Trump spoke only in general terms about foreign policy. He said the United States should not “be a nation builder,” repeated his line from the campaign that fighting the war in Iraq was “one of the great mistakes in the history of our country,” and said he has some “very definitive” and “strong ideas” about how to deal with the violent civil war raging in Syria. He declined to say what those ideas are despite several requests to do so.

“We have to end that craziness that’s going on in Syria,” he said.

The president-elect said that he had talked with President Vladimir V. Putinof Russia since winning the election, but he did not elaborate. He said it would be “nice” if he and Mr. Putin could get along, but he rejected the idea that any warming of relations would be called a “reset,” noting the criticism that Mrs. Clinton received after her attempts at bettering relations between the countries failed.

“I wouldn’t use that term after what happened,” Mr. Trump said.

Mr. Trump made a forceful defense of Mr. Bannon, whom he named as his chief strategist and who has drawn charges of racism and anti-Semitism. This summer, Mr. Bannon called Breitbart News, the website he led, “the platform for the alt-right,” a white nationalist movement.

Mr. Trump said Mr. Bannon had been dismayed at the reaction to his hiring.

“I’ve known Steve Bannon a long time. If I thought he was a racist or alt-right,” he said, “I wouldn’t even think about hiring him.”

Mr. Trump added: “I think he’s having a hard time with it because it’s not him. I think he’s been treated very unfairly.”

He also defended Breitbart, which has carried racist and anti-Semitic content, saying it was no different from The Times, only “much more conservative.”

Mr. Trump said he hoped to develop a “great long-term relationship” with President Obama, with whom he said he had an unexpected rapport. “I really liked him a lot, and I am a little bit surprised that I am telling you that I really liked him a lot,” he said.

And Mr. Trump gloated about defying the polls and the expectations of his own party to win the presidency, and boasted of how he had taken his revenge on Republicans who kept him at a distance and then lost their own races.

He said that one of them, Senator Kelly Ayotte of New Hampshire, would “love to have a job in the administration.”

“I said, ‘No, thank you,’” Mr. Trump said of Ms. Ayotte, who lost her Senate seat to Gov. Maggie Hassan of New Hampshire. “She refused to vote for me.”

He also criticized Representative Joe Heck of Nevada, who vacillated over supporting Mr. Trump after an 11-year-old recording surfaced in which Mr. Trump bragged in lewd terms about grabbing women without their consent.

“He went down like a lead balloon,” Mr. Trump said of Mr. Heck. “I said, ‘Off the record, I hope you lose.’”

He said Republican leaders felt indebted to him for his surprise victory.

“Right now,” Mr. Trump said, “they’re in love with me.”