As the conservative hawk begins speaking more publicly, he appears to be trying to pressure the White House into allowing some – or most – of his West Wing tell-all to be published. During an appearance on Monday night in Durham, North Carolina, Mr Bolton said he is unable to speak about many items grabbing headlines today, including whether Mr Trump acted inappropriately towards the Ukraine.
Asked by Duke professor Peter Feaver whether he agrees with Mr Trump's contention that his 25 July call with that country's president was "perfect," Mr Bolton went into book salesman mode.
"You'll love chapter 14," Mr Bolton replied.
He claimed, as he did throughout the talk, that he could not discuss the topic because the White House is still reviewing his book to ensure sensitive national security information is not made public. (White Houses under all presidents regularly conduct such reviews, sometimes to the frustration of employees-turned-author.)
Mr Bolton told an audience – media members were not allowed to record his remarks – that his version of the Trump team's official and shadow Ukraine policy efforts would be, if they make it into his book, "sprinkles on the ice cream sundae."
Mr Bolton, who has been panned over the years by Democratic lawmakers for his hawkish national security views and his fierce advocacy of the 2003 Iraq conflict, sold himself as an earnest public servant.
"This is this is an effort to write history, and I did it the best I can," he said on Monday night. "We'll have to see what comes out of the censorship."
Mr Bolton does not want potential readers to feel sorry for his treatment by Mr Trump, who fired him over policy differences and has called him, in so many words, a huckster just trying to cash in off his book. But Mr Bolton does want them to purchase his tome, which could hit racks as soon as 20 March.
"In my view, to pursue the right polices for America, I was willing to put up with a lot. I'm not asking for martyrdom because of that," he said. "I knew – think I knew – what I was getting into. I did it for 17 months. I did the best I could. You can judge the results by what the policies are."
On Mr Trump's attempts to befriend North Korean leader Kim Jong Un – with whom the president claims to be "in love" – Mr Bolton did not hold back. He said of Mr Trump's two summits with Mr Kim: "It was perfectly evident it was going to fail."
"There is not a single piece of evidence that the government of North Korea has made a strategic decision to give up the pursuit of nuclear weapons," he said.
On Iran, the former senior White House official said "I don't think we are applying maximum pressure," a swipe at the administration's contention its stiff sanctions amount to just that.
White House spokeswoman Stephanie Grisham did not respond to a request for a response to Mr. Bolton's Durham talk.
But late last month, Mr Trump claimed on Twitter that he "NEVER told John Bolton that the aid to Ukraine was tied to investigations into Democrats, including the Bidens."
"In fact, he never complained about this at the time of his very public termination," the president wrote in a 25 January tweet. "If John Bolton said this, it was only to sell a book."