In June 2020, less than five months before polling day, Donald Trump agreed to a “coup d’état” to remove his son-in-law Jared Kushner from control of his presidential re-election campaign and replace him with the far-right provocateur Steve Bannon.

The coup had support from Donald Trump Jr but according to a new book by the former Trump aide Peter Navarro it did not work, after Trump refused to give Kushner the bad news himself.

Fearing “family troubles if [he] himself had to deliver the bad news to … the father of his grandchildren”, Trump asked Bernie Marcus, the founder of Home Depot, a major Republican donor and a central player in the coup, “to be the messenger” to Kushner.

In Navarro’s telling, Kushner first insulted Marcus by skipping a call, then told Trump’s emissary “things were fine with the campaign, there was no way he was stepping down and, in effect, Bernie Marcus and his big moneybags could go pound sand”.

Navarro writes: “And that was that. And the rest is a catastrophic strategic failure history.”

In November, Trump lost the White House to Joe Biden.

With his wife, Ivanka Trump, Kushner was a senior adviser to Trump in the White House and on the campaign, essentially acting as a shadow chief of staff.

Before entering the White House, Navarro, with a Harvard PhD in economics, wrote a number of books attacking China (and liberally quoting a source whose name was an anagram of his own).

His new book, Taking Back Trump’s America: Why We Lost the White House and How We’ll Win It Back, will be published later this month. The Guardian obtained a copy.

Navarro’s dim view of Kushner permeates his new book: one section is titled Both Nepotism and Excrement Roll Downhill.

Navarro also took a central role in responding to the Covid-19 pandemic. He says planning for the campaign coup originated when Kushner told Fox News in April 2020 the pandemic would be over by the summer.

“In being so wrong,” Navarro writes, “Jared ‘Pangloss’ Kushner woke up” big donors who until then thought “Kushner and the Trump campaign would, at some point, get its ship together”.

Dr Pangloss is a character in Voltaire’s Candide, given to extreme optimism in the face of adversity.

Navarro reprints a journal entry for 25 June 2020 which describes a meeting in New York between Bannon and donors who “want[ed] Kushner and Brad Parscale [the campaign manager] out the door”. He adds: “Don Jr [and his girlfriend] Kimberly Guilfoyle feel the same way. This could be really interesting. It could also be our last chance for victory.”

According to Navarro, the plotters thought Bannon, who chaired Trump’s campaign in 2016, was the only operative who could steer him to re-election four years later.

The plotters also knew that Kushner would never agree to the change – Navarro says Kushner told him he wanted to “crush Bannon like a bug” – and that Trump resented Bannon for taking “too much credit for the 2016 win”.

Bannon was fired as White House strategist in August 2017, amid controversy over Trump’s supportive remarks about far-right protesters in Charlottesville, Virginia. Returning to Breitbart News, Bannon remained influential in Trump’s orbit.

On the page, Navarro risks Trump’s ire by criticizing his actions as president, at one point devoting six pages to outlining “why a president who is supposed to be one of the greatest assessors of talent … would make such bad personnel choices across so many White House and cabinet-level positions”.

He also writes that Trump could not have beaten Hillary Clinton in 2016 without Bannon, at the behest of another big donor, Robert Mercer, “coming in towards the end of the campaign and righting the Kushner ship”.

In 2020, Navarro says, he conquered his “trepidations” about angering Trump and pressed ahead with the anti-Kushner plot. Navarro says he set up and attended a White House meeting between Trump and Marcus at which Trump “readily agreed with Bernie that Jared had to be replaced with Steve”.

But there was another problem, again at odds with the ruthless image Trump constructed on The Apprentice, his NBC reality TV hit, in which his catchphrase was “You’re fired!”

As has been extensively documented, Trump in fact does not like firing people.

“Rather than being shot himself,” Navarro writes, Trump “asked Bernie to be the messenger” to Kushner.

Marcus “accepted the mission, albeit grudgingly”. The mission failed. Parscale, the campaign manager under Kushner, was removed in July but the son-in-law stayed in control.

Navarro played a central role in Trump’s attempts to overturn his election defeat, outlining a plan called the “Green Bay Sweep” which was meant to block certification of Biden’s win.

In November, Navarro will stand trial. He is charged with contempt of Congress, for refusing to comply with the January 6 investigation. He faces up to two years in jail. The judge in the case refused a request to hold the trial next April, so Navarro could market his new book.