The government shutdown is just the latest and highest-profile example of Mr. Trump sounding assertive but gaining little, at least so far. American allies, diplomats said, have more a sense of resignation than fear in dealing with him. The list of threats from Mr. Trump is long, but the number of times he has followed through is exceedingly short.
“He is playing a role, and the role, much like on ‘The Apprentice,’ was of the strong, able character, but it’s a role,” said David Axelrod, a senior adviser to President Barack Obama. “Every foreign leader and every practicing politician has taken a measure of him and understands the basics, that he responds to strength and there’s not a lot behind the facade.”
In recent months, Mr. Trump has had tense conversations with, among others, Prime Minister Theresa May of Britain and President Emmanuel Macron of France, who has felt trolled by Mr. Trump over the state of the French economy, people familiar with the conversations said.
The German chancellor, Angela Merkel, has indicated to people that she does not consider Mr. Trump a serious person to talk with. His get-tough, tariff-driven approach to bringing China to heel has had mixed results at best, hurting some American industries, and sending markets plunging. Even on one of his most prominent issues where he drew bright lines and promised severe consequences — the renegotiation of the North American Free Trade Agreement with Canada and Mexico — Mr. Trump did not walk away with anything close to a windfall.
Instead, most trade experts said the revised trade accord included modest substantive changes that will benefit the United States, and others said the biggest difference may be symbolic: a change in the name, to the United States-Mexico-Canada Agreement. Congress has yet to vote on that pact.
But there is one place where Mr. Trump’s fear tactics have been an unqualified success: among Republicans. Mr. Trump has held an iron grip on the Republican base, making it difficult for fellow party members, who also rely on those core voters, to oppose him.
“There is no constituency within a party that is so dominated by one individual that is charting a course with the opposition unless you want to be a former lawmaker,” said Josh Holmes, a Republican strategist who is close to Mr. McConnell.