If he seemed all over the map, he made clear on Monday, as he wrapped up days of diplomacy, that the world would just have to get used to it. He likes leaving negotiating partners, adversaries, observers and even allies off balance.

“Sorry!” he told reporters, sounding anything but apologetic. “It’s the way I negotiate. It’s the way I negotiate. It’s done very well for me over the years, and it’s doing even better for the country.”

The way he negotiates at times involves facts that may not be facts, statements that may not have been said and episodes that may not have occurred. And at times, he denied saying what he had said.

On Sunday, he said he had “second thoughts” about escalating the trade war with China, only to have staff members later insist that his only regret was not escalating it more. By Monday morning, he was ratcheting back the rhetoric and predicting a deal with Mr. Xi, whom he pronounced a “great leader” four times.