Experts inside and outside the American government believe that Mr. Kim’s ultimate goal is to have his country recognized as a nuclear power even as he offers enough concessions — some potentially largely symbolic — to press the United States into easing crippling economic sanctions.
Analysts who study North Korea’s diplomatic patterns say there is cause for concern over Mr. Kim’s overtures, given his murky motives and his apparent effort to use the concessions to try to achieve the upper hand in the negotiation process.
North Korea has a long history of not abiding by promises to curtail its nuclear program, and Mr. Todd on his program reflected skepticism among former and some current White House officials that Mr. Kim will actually follow through on any vow to dismantle the North’s primary nuclear test site or stop nuclear weapons testing.
Some officials worry that Mr. Trump may be so eager to reach a historic deal that he will be lured into an agreement that falls short of the denuclearization of the Korean Peninsula that global powers have demanded.
Mr. Short said the administration had “cautious optimism” about the North Korea talks, which are expected in the next month or two. But he said the president would not relent on his “maximum pressure” campaign against the North until it denuclearized.
Asked what “denuclearization” meant to the two sides, Mr. Short said that they would have to hash it out, but that the American view was that it would mean “full denuclearization.”
Mr. Trump, perhaps sensitive to any suggestion that he could be duped by a wily North Korean leader, sought to project an air of only-time-will-tell caution.
“We are a long way from conclusion on North Korea, maybe things will work out, and maybe they won’t,” Mr. Trump wrote.
Later in the day, the president had a word for those who had publicly counseled him to proceed warily.
“Funny how all of the Pundits that couldn’t come close to making a deal on North Korea are now all over the place telling me how to make a deal!” he tweeted.