In 2009, then US Vice President Joe Biden came to Munich to "press the reset button" with Russia. A decade later he came again to offer the world better relations, this time with his own country.

Promising that "America will be back" once Donald Trump leaves office, Biden won a standing ovation at the Munich Security Conference from delegates who find the president's brusque foreign policy stance hard to like.

But their elation also exposed the weakened state of Western diplomacy in the face of Trump's assertiveness, according to European diplomats and politicians who were present.

Biden's successor, Mike Pence, was met with silence at a reception in the palatial Bavarian parliament on Friday evening after he delivered his signature line: "I bring you greetings from the 45th president of the United States, President Donald Trump."

His four-day trip to Europe succeeded only in deepening divisions with traditional allies over questions such as Iran and Venezuela and offered little hope in how to deal with threats ranging from nuclear arms to climate change, diplomats and officials said.

Misgivings about Washington's role in the world are being felt by ordinary people as well as foreign policy specialists. In Germany and France, half the population see US power as a threat, up sharply from 2013 and a view shared by 37 percent of Britons, the Washington-based Pew Research Center said in a report before the Munich foreign policy gathering.

Asked about European anxiety over Trump's leadership style, a senior US official on Pence's Air Force Two plane said the vice president's Munich conference speech on Saturday at the Hotel Bayerischer Hof would "help give them a different perspective".

"TIT-FOR-TAT"

But if the Europeans did not like the "America First" message, there was no concerted response to it. German Chancellor Angela Merkel was on her own after a last-minute cancellation by French President Emmanuel Macron.

That caused some to lament the failure of the West to uphold the rules-based international order that Washington itself championed in the 70 years that preceded the arrival of Trumpin the White House.

"The tit-for-tat logic is unfortunately prevailing ... I think that takes us back to the question of enlightened leadership," said Thomas Greminger, secretary general of the Organization forSecurity and Co-operation in Europe, a security and human rights watchdog.

"We need leaders again who do not believe exclusively in short-termism," he told Reuters.