“You have a president who is willing to stand up to the Washington foreign policy establishment in a way that Trump or Obama or George W. Bush were not,” said Vali R. Nasr, a former Obama administration official who teaches at the Johns Hopkins School of Advanced International Studies. “To me, that does require introspection on the part of the foreign policy establishment.”

While Mr. Biden may have antagonized foreign policy elites, his determination to extricate the United States from costly entanglements overseas plays better with average Americans. While the harrowing images of the evacuation have damaged his approval ratings, polls suggest that many, if not most, share his conviction that the country does not have a compelling reason to stay in Afghanistan…

For all their differences, Mr. Nasr said there was a thread of skepticism about military intervention that connected Mr. Obama’s reluctance to deploy troops, Mr. Trump’s isolationist slogan, “America First,” and Mr. Biden’s blunt declaration that helping the Afghan people was not a vital national security interest of the United States.

The president, Mr. Nasr said, has also shown a willingness to disregard the views of European allies, a factor that helps account for the frustration in London, Berlin and other capitals, where Mr. Biden’s election had been celebrated after Mr. Trump’s browbeating. The NATO campaign in Afghanistan was a credit to the solidarity of the alliance, which made Mr. Biden’s lack of consultation all the more stinging.