Robert Costa (left) in a panel discussion in 2017 and Bob Woodward at the 2019 PEN America Literary Gala in New York. The two have authored a book about the transition between the Trump and Biden administrations.

Robert Costa (left) in a panel discussion in 2017 and Bob Woodward at the 2019 PEN America Literary Gala in New York. The two have authored a book about the transition between the Trump and Biden administrations. / AP

Updated September 20, 2021 at 12:03 PM ET

Bob Woodward is back with another book about former President Donald Trump, this time co-authored with fellow Washington Post reporter Robert Costa. This book focuses on the transition between the Trump and Biden administrations.

Peril has already made headlines for an early and explosive revelation: Gen. Mark Milley, chairman of the Joint Chiefs of Staff, reportedly called his Chinese counterpart to reassure him that the U.S. was not planning an attack in the final months of Trump's term. The report also details Trump's response to the Jan. 6 insurrection, his efforts to challenge the presidential election results and other scenes from inside the White House.

But NPR political correspondent and editor Ron Elving writes the book "turns out to be just as much about President Biden and how he got to be Trump's successor."

Costa spoke to Morning Edition's Steve Inskeep about the book and what he learned from taking an inside look at the fraught transfer of power.

"It's important to understand, based on spending the last nine months doing this with Bob Woodward, how much of a national security emergency this country faced during the transition, around Jan. 6," Costa said. "Our book carefully documents how Chairman Milley, within the bounds of his responsibility, was trying to contain a situation that he felt could fall way out of the norm: that the Chinese could misinterpret what was happening, that President Trump — he believed, based on our reporting — was in serious mental decline. This was a situation that we all know was a domestic crisis but also a security crisis."

Some of the other topics Costa and Inskeep covered include former Vice President Mike Pence's election certification dilemma, former Attorney General William Barr's relationship with Trump and what various prominent Republicans think about Trump's role in GOP politics.

Costa noted that politicians such as Sen. Lindsey Graham still see the former president as the future of the party despite their earlier criticisms.

"That's partly why we called the book Peril," he said. "Woodward and I realized that this system, the American system and also the Republican Party, [were] tested to the brink, and that peril remains. President Trump's a political figure who remains on the scene with immense political capital."

This story originally published in the Morning Edition live blog.

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