Those diplomats are increasingly concerned that the White House and senior State Department leadership do not have their backs, particularly after Trump’s allies launched a whisper campaign that ended in the recall of Marie Yovanovitch as U.S. ambassador to Ukraine.

They also worry the president’s decision to withdraw American troops from northern Syria — abandoning longtime Kurdish allies who fought the war against the Islamic State — will cause other allies to think twice about partnering with the United States.

“We have squandered our global leadership, alienated our friends and emboldened our enemies,” said one U.S. ambassador, who asked not to be named to provide a candid assessment. Morale in recent weeks, the ambassador said, “is at a new low, although I am not sure it could fall much lower than where it has been for the past three years.”