But critics say that his behavior overlooks the fact that America’s most durable alliances are in Europe, not the Middle East, and that Europeans are not likely to buy Mr. Trump’s bluster.

“Everybody sees that he’s trying to be a tough negotiator with the Europeans, whom he apparently views as a bunch of weaklings,” said Daniel Gros, the director of the Center for European Policy Studies, a think tank in Brussels. “But nobody sees any use in firing back. They think there will be very little action on trade. Ultimately, they think it’s harmless.”

On Friday evening, White House officials reported that Mr. Trump’s first day of meetings with the leaders of Britain, Germany, France, Italy, Canada and Japan had been lively and productive. The leaders discussed terrorism, North Korea, Iran, trade and climate change, they said, and there was even hope that the United States and Europe might stake out some common ground on the future of the Paris climate accord.

Gary D. Cohn, the director of the National Economic Council, compared the atmosphere to a family dinner with his three daughters, in which all those at the table are confident about their views. “There was a lot of what I would call pushing and prodding,” Mr. Cohn said, “I think the president learned how important it is for the United States to show leadership.”

Still, the tone was a notable departure from the visit to the Middle East, where Mr. Trump scrupulously avoided lecturing the Saudis on human rights or the Israelis on their construction of Jewish settlements in the West Bank. His harsh statements in Europe suggested that he could be most divisive American leader to join this rarefied club since it was first organized in 1975.