At a news conference at Camp David Jan 6., President Trump responded to a question from a reporter about a tweet he posted on his mental state earlier that day. (The Washington Post)

The most astonishing aspect of the response to Michael Wolff’s book is that anyone is surprised. President Trump’s unfitness for office was obvious long before he was elected. Once he moved into the White House, the destructive chaos of his administration was there for all to see. Future historians will scratch their heads to figure out why it took this particular book to break the dam of denial.

None of this takes anything away from Wolff’s achievement in “Fire and Fury.” On the contrary, he deserves our thanks for creating Trump’s “emperor has no clothes” moment, even if this point should have been reached before, say, Nov. 8, 2016. Trump’s tweets on Saturday pronouncing himself “a very stable genius” only underscored the damage Wolff has done and Trump’s dumbfounding insecurity.

But Wolff alone cannot bring this presidency crashing down, given how many Republicans still seem determined to protect Trump. Even as the news was dominated by Wolff’s revelations, Republican Sens. Charles E. Grassley and Lindsey O. Graham made a criminal referral to the Justice Department on Friday — and not against anyone who might have colluded with Russia. Instead, they urged investigation of Christopher Steele, the former British spy who authored an explosive dossier including information that Trump may have been compromised by Moscow.

Fortunately, this will not derail special counsel Robert S. Mueller III’s probe, but the episode was one of many signs that Republican leaders in Congress are sticking with Trump in the face of the damage the president’s increasingly obvious and glaring shortcomings are doing to our country. Over the weekend, Republican leaders trooped up to Camp David to meet with Trump and pledge their allegiance to a common agenda.

To chart a path forward from here, it’s important to see why Trump has maintained enough support, or at least acquiescence, to keep himself in office.

The first key is his phony populism, with an emphasis on both words.

Trump will continue to try to rally what base he has left with tweets about kneeling NFL players, immigrants, law and order and “political correctness.” He will keep attacking Hillary Clinton, the surest sign of his weakness, since his own record has done little to draw Americans his way. He needs targets to make his enemy-of-my-enemy-is-my-friend approach work.

But it’s not working as well as it used to. Trump’s policies have shown that his true commitments are to himself and to other very wealthy people and corporate interests. The broad unpopularity of his tax cut is a sign that his flimflam has not deceived voters as to where his heart and his bank account lie.

His other policies, reflected in his slew of executive actions, have weakened federal protections for the environment, for workplace safety and worker pay, for civil rights and for small investors.

Last week alone, in the midst of the swirl around Wolff’s book, the administration moved to open nearly all of our offshore waters to drilling even as the Department of Housing and Urban Development suspended an Obama-era rule requiring communities to address residential segregation. And the Justice Department, undercutting conservative states’-rights rhetoric, renewed enforcement of federal marijuana laws despite state legalization statutes.

Trump aides and administration members attacked Michael Wolff, his new book "Fire and Fury," and Stephen K. Bannon on Jan. 7. (Jenny Starrs/The Washington Post)

In response to what is little more than a traditional right-wing agenda, there has been a marked erosion of loyalty to Trump among voters who thought they were casting ballots for a populist and are getting ideological and plutocratic policies instead. A Pew Research Center survey last month found Trump losing ground particularly among whites without college degrees and white evangelical Christians, groups whose devotion Trump counts on.

On the other hand, the more Trump proves his populism to be phony and behaves like a traditional Republican, the more the congressional GOP will want to prop him up. Trump’s break with Stephen K. Bannon, the nemesis of the Capitol Hill crowd, will bring the president and the elected conservative establishment closer, and Bannon’s statement on Sunday attempting to soften his comments to Wolff without retracting them is unlikely to change this.

What might be called the Wolff Effect will thus be paradoxical. It could strengthen the bonds between Republican politicians and Trump at the very moment when everyone else is coming to terms with how dangerous it is to have a president who is so uninformed and unstable. In the meantime, more traditional journalists will carry on their painstaking work, piling up evidence that Trump did all he could to block a legal accounting for the methods that helped get him to the White House in the first place.

We should have gotten here sooner. But far better late than never.

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