Donald Trump has already chased one Attorney General out of his administration. Can he go two-for-two? William Barr has warned people close to Trump, the Washington Post reported last night, that he meant what he said to ABC News last week. Barr told ABC that Trump’s tweets about Department of Justice cases make it “impossible” to do his job. “Impossible,” as in Barr will find something else to do rather than be Attorney General:

Attorney General William P. Barr has told people close to President Trump — both inside and outside the White House — that he is considering quitting over Trump’s tweets about Justice Department investigations, three administration officials said, foreshadowing a possible confrontation between the president and his attorney general over the independence of the Justice Department.

So far, Trump has defied Barr’s requests, both public and private, to keep quiet on matters of federal law enforcement. It was not immediately clear Tuesday whether Barr had made his posture known directly to Trump. The administration officials said Barr seemed to be sharing his position with advisers in hopes the president would get the message that he should stop weighing in publicly on the Justice Department’s ongoing criminal investigations.

“He has his limits,” said one person familiar with Barr’s thinking, speaking on the condition of anonymity, like others, to discuss internal deliberations.

If Barr has his limits, one wonders why he took the job at all. His predecessor got publicly abused for well over a year on Twitter and elsewhere by Trump for his recusal decision. One has to figure that Barr set the limits rather broadly in the first place just to have taken the job at all. On the other hand, Barr may have anticipated personal disagreements turning nasty in public, not commentary on specific cases and Twitter demands for DoJ actions that call the integrity of prosecutions into questions. That would be a different kettle of fish for an institutionalist like Barr, and almost certainly would cross his “limits.”

Last night, Barr’s spokesperson denies any plans for resigning:

Addressing Beltway rumors: The Attorney General has no plans to resign.

— Kerri Kupec DOJ (@KerriKupecDOJ) February 19, 2020

No specific plans, probably. However, an AG does not go on national television to complain about the Tweeter in Chief without at least considering his post-DoJ career. All Jeff Sessions did was recuse himself from the Russia probe after his memory lapse about a brief conversation with Sergei Kislyak threatened to make him a witness in the investigation, if not a subject of it, and Trump had a two-year meltdown over it. Sessions didn’t go out of his way to tell his boss to stop tweeting and stop bothering him, which makes Barr’s ABC comments quite the striking turnaround from 2017-18 in POTUS-AG relations.

Barr’s in a different position than Sessions was, however. That was Sessions’ dream job, but Barr’s done it before and under more comfortable circumstances. Barr didn’t give up a cushy Senate seat to take the job, nor does he want one. Barr doesn’t have any obvious political ambitions; when he leaves, he’ll either go back to private practice or retire to work on his memoirs. It’s tough to have leverage as a boss when the subordinate doesn’t have much investment in career growth.

Trump needs Barr more than the other way around, and both Barr and Trump know it. At the beginning of his presidency, Trump had the luxury of appointing a partisan MAGA cheerleader to run the DoJ, but now he needs someone with arms-length distance for the credibility needed to conclude the John Durham probe into the Russiagate investigation. Until all of that concludes, Trump can’t afford to replace Barr, not even if Barr leaves on his own. If Trump squeezes Barr out before the election, the confirmation process will likely turn into an impeachment trial by proxy, and the White House almost certainly knows that much.

Barr probably doesn’t have any plans to resign, but he certainly hinted at the possibility during his ABC interview. Barr’s probably gotten more specific about his options with White House officials before and after that as well. Trump can do what he likes, but Barr doesn’t have to stick around for it, either.