Early this morning, the Guardian reported on the contents of a new book by journalist Michael Wolff. According to the paper’s story, Steve Bannon spoke to Wolff on the record about his experiences in the Trump campaign and the Trump White House, and he sounded more like a member of the #Resistance than the president’s former chief strategist.

According to Wolff, Bannon called Donald Junior’s now-infamous June 2016 meeting with a Russian lawyer in Trump Tower “treasonous” and “unpatriotic.” He said that Trump Jr. should have “called the FBI immediately” after the Russians first made contact. He also speculated that Trump knew about the meeting, declaring in typical Bannon language that “the chance that Don Jr. did not walk these jumos up to his father’s office on the 26th floor is zero.” And he speculated that the Mueller probe would focus on money laundering, predicting that “they’re going to crack Don Junior like an egg on national TV.”

It didn’t take long for President Trump to respond with one of the most blistering statements of his presidency so far:

Steve Bannon has nothing to do with me or my Presidency. When he was fired, he not only lost his job, he lost his mind. Steve was a staffer who worked for me after I had already won the nomination by defeating seventeen candidates, often described as the most talented field ever assembled in the Republican party.

Now that he is on his own, Steve is learning that winning isn’t as easy as I make it look. Steve had very little to do with our historic victory, which was delivered by the forgotten men and women of this country. Yet Steve had everything to do with the loss of a Senate seat in Alabama held for more than thirty years by Republicans.

Steve doesn’t represent my base — he’s only in it for himself.

Steve pretends to be at war with the media, which he calls the opposition party, yet he spent his time at the White House leaking false information to the media to make himself seem far more important than he was. It is the only thing he does well. Steve was rarely in a one-on-one meeting with me and only pretends to have had influence to fool a few people with no access and no clue, whom he helped write phony books.

We have many great Republican members of Congress and candidates who are very supportive of the Make America Great Again agenda. Like me, they love the United States of America and are helping to finally take our country back and build it up, rather than simply seeking to burn it all down.

If this statement marks the definitive end of the Trump–Bannon relationship — as Erick Erickson notes, there’s still reason to be skeptical that it will — then Trump just made one of the best decisions of his presidency, for at least three reasons.

First, Bannon is the public figure who has done more than any other person to introduce the evil alt-right into mainstream American life. He bragged about turning Breitbart into the “platform” of that movement, backed one of its most prominent politicians in Paul Nehlen, and relentlessly promoted its foremost apologist, the noxious Milo Yiannopoulos. He was also reportedly one of the driving forces behind perhaps the worst moment of Trump’s term so far: the president’s decision to equivocate following the alt-right rally and terrorist attack in Charlottesville, Va.

Second, Bannon is the primary pseudo-intellectual advocate of the incoherent, destructive nationalist–populist ideology that he tried to transform into “Trumpism.” His isolationism would harm American national security, his protectionism would harm the American economy, and his populism veers dangerously into the realm of white-identity politics. If his influence over the president is truly at an end, the GOP will have a real chance to restore itself as a party of conservative ideas.

Third, Bannon’s fall gives space for better men and women to rise. There are good and decent people who work in this White House, people who haven’t merely latched on to Trump to leech off his fame and climb to power. There are conservatives who seek to use this historical moment to advance the common good, and there are pragmatists who understand that divisiveness is not in the nation’s — or Trump’s — best interests. There is never any guarantee that virtue and good policy will prevail, but decisively breaking with a man so vile is unquestionably a positive step.

Questions about Trump’s presidency weren’t limited to questions about Trump himself. As he rose to power, other people would obviously rise right alongside him. Their identities and characters mattered, and still do, because their mere proximity to Trump gives them real influence. When Trump rose, Bannon rose, and Bannon is one of the worst men in American politics. Today represents a perfect example of addition by subtraction. Trump did well in rejecting Bannon. Here’s hoping he holds to that decision and replaces Bannon’s voice with the better voices that still remain.