When President Donald Trump Friday asked for resignation letters from 46 U.S. attorneys, attention focused on just one of them: Preet Bharara, the country’s most feared and revered prosecutor and the inspiration for the hit show Billions.

It’s normal for new presidents to axe the previous administration’s appointees, but then President-elect Trump had told Bharara in November he’d stay on the job, an announcement cheered by Democrats and Republicans alike and seen as a sign that the new boss might govern more moderately than he had campaigned, making decisions based on merit and wisdom rather than ideology and brute partisanship.

Psych.

Trump’s stunning reversal, which came without explanation, was a blow to the nation and a gut punch to New York.

Without question, Bharara pushed the envelope with the scope and tactics of his prosecutions, but he largely avoided criticism from the press and the public because of the evenhandedness with which he pursued wrongdoing. In no area was this impartiality clearer than in his takedowns of dirty New York politicians.

Less than two weeks apart, Bharara secured the convictions of both the Democratic leader of New York’s State Assembly and the Republican leader of its Senate. Before Bharara had trained his sights on Albany, New York’s capital had degenerated into an orgy of graft and cronyism.

He wasn’t done. Bharara has already indicted one of Gov. Andrew Cuomo’s closest aides as part of an ongoing investigation, and just three weeks ago his office had questioned Bill de Blasio in a long-running probe into pay-for-play questions about the mayor and his administration.

While these investigations will not likely evaporate under Bharara’s successor, it’s a near certainty that Cuomo and de Blasio slept more peacefully Friday night than they had in some time.

Why would Trump potentially derail investigations into de Blasio, who is currently campaigning for reelection on a platform of opposing him, and Cuomo, who has been stoking rumors that he’ll seek the Democratic nomination for President in 2020?

We don’t have an answer yet, but we know New Yorkers have lost one of their greatest public servants at a time when we desperately need him.

It must weigh heavily upon Bharara not being able to see his investigations through to the end. Asked to resign, he refused. So on Saturday he was fired.

The following day, he tweeted, “By the way, now I know what the Moreland Commission must have felt like,” a lacerating reference to the blue-ribbon commission Cuomo had appointed in 2013 to probe Albany corruption and then abruptly shut down when it bucked Cuomo’s control and proved too adept at following its assignment. Bharara then subpoenaed its records, and began a fearless dive into the pits of New York corruption that continued until this weekend.

For years there’s been chatter that Bharara’s next act would be as a candidate, but no reason to take this scuttlebutt seriously as long as Bharara was at his self-professed dream job.

Now he’s had that yanked away. And when he sees the culture of corruption in New York, he’ll have to grit his teeth and bear it like everyone else. Or not.

Fortunately, there is something Bharara, a Democrat, can do to complete his work and open a great new chapter in his storied career: run for governor next year against Cuomo.

A Bharara win would bring both a literal and symbolic end to a disgraceful era of New York politics. He would also be in one of the most potent positions in the country to oppose the Trump administration’s overreach. And, of course, getting fired by Trump amounts to an endorsement for the Democratic voters here who would decide that race.

The Democratic Party desperately needs new leaders of true integrity, and so too does the nation. Today, Preet Bharara is unemployed. Stay tuned.