Why would anyone trust Chris Christie?

Ask any publisher. Two cardinal rules of non-fiction writing are obvious and unambiguous: Know your strengths. Know your audience.

No offense to the very smart folks at Threshold Editions, an imprint of Simon & Schuster and my own publisher, but did anyone there ask former New Jersey Gov. Chris Christie if he could identify either?

Threshold just announced his new book, coming in November: “Republican Rescue: Saving the Party from Truth Deniers, Conspiracy Theorists and the Dangerous Policies of Joe Biden.”

According to the press release: “As a Republican insider, Christie feels compelled to weigh in on the past four years, but especially the past few months, and explain how these falsehoods, and the grievance politics they support, cost his party the House, the Senate and the White House in two years, for the first time since Herbert Hoover.”

On its face, this is a correct diagnosis of the GOP’s problems. The non-stop falsehoods and destructive grievance politics (not to mention the racism, ignorance, corruption, cronyism, graft, greed, incompetence and abuse of power) certainly contributed to Donald Trump and Republicans losing the White House and both chambers of Congress in just one short term.

But let’s be honest, asking Christie to diagnose the structural inefficiencies of the GOP is like asking an earthquake to diagnose the structural inefficiencies of the pile of rubble it just created.

Christie’s support of Trump came early and often. He was one of the first leading Republicans to endorse him in 2016, and voted for him twice. Christie helped prep Trump for his debates against then-candidate Joe Biden in 2020.

Christie has defended Trump an untold number of times over the course of Trump’s ignominious presidency.

He defended Trump against claims that he was racist, whether it was regarding his birtherism, his comments about a Hispanic judge or calling Nazi-sympathizers at a Charlottesville protest “very fine people.”

He’s explained away Trump’s pathological penchant for lying, once saying, “People in public life often say things that turn out not to be true.”

And he’s justified some of Trump’s worst, most deleterious and undemocratic policies, including the travel ban aimed at majority-Muslim countries, which Christie applauded as, essentially, not as bad as it could have been.

It’s really hard to trust the diagnosis when the diagnostician has, at times, been on the side of the disease.

More from the publisher’s release:

“Christie delivers a frank insider’s account of [the 2020] election and the tragic descent of some members of the Republican Party into cowardice and madness…”

Insider accounts can be very useful. But it’s a comically convenient framing of Christie’s role in the Trump saga. He wasn’t merely an observer, he was a participant, and one whose behind-the-scenes and front-facing work enabled and emboldened the Trump administration and other Republicans to ultimately secure their own demise.

Defending Trump, even around the edges at times, conditioned the very environment Christie is presumably lamenting — one that resulted in the spread of dangerous conspiracy theories, baseless claims of election fraud, the rise of GOP kooks like Marjorie Taylor Greene and an insurrection at the U.S. Capitol.

There’s a difference between being an insider and a co-conspirator. Christie can offer an “insider’s account” of the GOP’s self-destruction in the same way the getaway driver can offer an “insider’s account” of a bank robbery.

Finally, and most eye-rollingly, the book will offer “no-nonsense solutions for how to recover the party’s image and integrity, and how to beat back the ultra-liberal policies of Joe Biden’s Democrats.”

No one — I mean no one — who said they supported the president and voted for him twice, who dismissed Trump’s nakedly racist and divisive rhetoric and policies, who defended his lies and lying, who just this January said, “No, I have no second thoughts in doing what I did in supporting him,” is in any position to help “recover the party’s image and integrity.”

Christie might argue that he’s also been quite critical of the former president, which is true. He’s often rebuked Trump’s temperament, his tweets, his bad hiring decisions, his incompetence and his policies over the years he was president.

To Christie, this bolsters his reliability as a caller of balls and strikes. But to the rest of us it begs the question: Given all those concerns, how could he have continued to support Trump, right through to the bitter end?

Wanting it all ways doesn’t make you particularly trustworthy. The GOP does have many problems. It needs prescriptive solutions from people willing to say what might be political inconvenient at the moment. But not from any of the people who aided and abetted the president and the party’s road to destruction.

S.E. Cupp is the host of “S.E. Cupp Unfiltered” on CNN.

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