• Guy Snodgrass, author of the book “Holding the Line: Inside Trump’s White House with Secretary Mattis,” told Insider, “Absolutely, Mattis did not want me to write this book.”
  • Mattis’s assistant gave a statement to Politico about the book, saying that in writing it, Snodgrass had “surrendered his honor.”
  • But Snodgrass told Insider that he’s proud of the book, which includes some shocking behind the scenes moments, like US President Donald Trump implying that no one “gives a s— about Afghanistan.”
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Cmdr. Guy Snodgrass, a retired naval aviator, former TOPGUN instructor, and speechwriter for Gen. James Mattis, knew the former Secretary of Defense wouldn’t like his new book, “Holding the Line: Inside Trump’s White House with Secretary Mattis.”

“Absolutely, Mattis did not want me to write this book,” Snodgrass told Insider this week. Mattis, when asked about his reaction to the book by Politico, issued a harshly-worded statement through his assistant, Candace Currier.

“General Mattis hasn’t read the book and doesn’t intend to,” Currier told Politico.

“Mr. Snodgrass was a junior staffer who took notes in some meetings but played no role in decision making. His choice to write a book reveals an absence of character,” Currier told Politico via email.

Snodgrass "surreptitiously taking notes without authorization for a self-promoting personal project is a clear violation of that trust, and while he "may receive a few brief moments of attention for this book. But those moments will be greatly outweighed by the fact that to get them, he surrendered his honor."

"I stand behind everything in the book. I'm very pleased with how it turned out," Snodgrass told Insider, adding that he thinks the book gives the public an important look into the defense decision-making process and understand "what the heck is going on behind closed doors."

"I was very disappointed by Mattis's response" to the book, Snodgrass said.

Snodgrass's book is full of astonishing tidbits, like Trump's profane reaction to a mission to provide aid to Afghanistan and his affinity for visual information, as well at Mattis's strained relationship with former national security advisor H.R. McMaster - what he calls a "first-person account" of what it was really like behind the scenes.

But Mattis has been notably taciturn about his tenure in the White House, which ended in December of 2018, the first time US President Donald Trump decided to announce a troop pullout from Syria.

Although his resignation letter acknowledged a divergence of opinion with Trump - one of several - he told Atlantic editor-in-chief Jeffrey Goldberg in a recent interview, "If you leave an administration, you owe some silence. When you leave an administration over clear policy differences, you need to give the people who are still there as much opportunity as possible to defend the country." In the same piece, Goldberg called "Call Sign Chaos" "a 100,000-word subtweet" - ostensibly of President Trump. Insider reached out to Mattis for this story, but did not receive a response by press time.

Snodgrass, who left the administration because of infighting among other members of senior staff, told Insider he remains proud of his office's work during the administration - they came up with the first defense strategy in a decade, beefed up the defense budget, and saw ISIS's physical caliphate destroyed.

But, he said, "It was certainly the hardest time of my life."