With that in mind, I told him that I thought what he was saying was new and interesting and that I wanted to interview him about it. He said he liked the idea and promised that we would talk after he finished lunch. I went back to my table with Mr. Ruddy and two other guests he had for lunch: Andrew J. Stein, a former Manhattan borough president, and Lee Lipton, a local restaurant owner.

Five minutes later, I heard the president call my name.

"Michael, come on, Michael," he said as he stood up.

"Come on, sit over there," he said as he motioned to a large empty table.

We sat down next to each other, I asked whether he was O.K. with me recording, he agreed and we were off. Mr. Trump immediately told me that there was no collusion between his associates and Russia's effort to influence the election — something he would repeat 15 more times during the interview.

It is unusual to land an interview with the president, but even more rare for a reporter to get him one-on-one. I knew that what I was doing was not going to go over well with the White House press office, which hates being blindsided by the president making news. But for much of the next half-hour, Mr. Trump and I sat alone.

During our conversation in July, I learned the challenges this president poses in interviews. He can jump from an issue like the Russia investigation to a policy matter before going off on a tangent about something like his golf game. If you try to interrupt him, he often continues talking. Given this, I employed a strategy in which I asked questions about the most pressing issues of his presidency and then allowed him to talk.

Some readers criticized my approach, saying I should have asked more follow-up questions. I believed it was more important to continue to allow the president to speak and let people make their own judgments about his statements. It was the best way to learn as much as possible about the president's mind-set and his views on issues like North Korea.

In the interview, the president did make news. He contradicted members of his own party, saying he believes the special counsel, Robert S. Mueller III, will treat him fairly. He said for the first time explicitly that he had gone soft on trade with China in the hopes that Beijing would help put pressure on North Korea to stop its nuclear weapons program. And he said that he never thought Roy Moore would win the Senate race in Alabama and that he had endorsed Mr. Moore only out of obligation.

At the end of the interview, Mr. Trump, who had asked about my golf game, told me that I should go out and play his course that afternoon. I told him I would not do that and I needed to file a story off the interview on deadline. He asked me to treat him fairly, we shook hands and I headed for my rental car. As I drove away from the club, I called my editors to tell them I had just spent half an hour alone with the president.