Another day, another embarrassing foreign policy circus in the nation’s capital that can only further erode trust in American leadership at home and abroad. At its center is Rex Tillerson, who traded his job as top dog at the oil giant ExxonMobil to become secretary of state, only to find himself substantively and personally undercut by President Trump as recently as Sunday on the issue of Korea, where Mr. Tillerson wanted negotiations as Mr. Trump threatened war.

On Wednesday, after NBC News reported that Mr. Tillerson was on the verge of resigning last summer, the secretary quickly called a news conference in which he asserted that he never considered doing so, though he did not personally deny a report that he had grown so disenchanted with the man in the Oval Office that he once called him a “moron” at a Pentagon meeting with the national security team and cabinet officials. Mr. Tillerson was said to be particularly upset by Mr. Trump’s highly politicized speech to the Boy Scouts of America, an organization the secretary once led. Various other Trump officials reportedly urged him to stay on at least until the end of the year, and Vice President Mike Pence counseled him on ways to ease tensions with the president.

The conflicts are numerous and mounting. Last week, in Beijing, Mr. Tillerson described efforts to explore contacts with North Korea over the nuclear issue, only to have Mr. Trump scorn the initiative as a waste of time, leaving the impression that he was focused mainly on military options. In June, Mr. Tillerson called on Saudi Arabia and other gulf states to ease their blockade of Qatar, only to have Mr. Trump endorse the crackdown. The Trump administration has twice certified that Iran is complying with the terms of the nuclear deal that was one of former President Barack Obama’s major diplomatic achievements. Mr. Trump has left little doubt about his contempt for the deal.