(CNN) - John McCain wanted to give this speech about Senate dysfunction before his brain cancer diagnosis last summer.
Then, his longtime aide, speechwriter and friend Mark Salter got a call from McCain with a sudden urgency
"’You coming out here? What's the story,’” Salter recalled of his conversation with McCain. “And I said, ‘Yeah, here's what I want to say in the speech.’ And I said, ‘have you gotten the results back.’ You know, he goes, ‘it's not good.’"
Salter rushed to Arizona. They finished the speech on the plane back to D.C.
"They all stayed in their chairs for his speech. That had never happened in his career and it meant a great deal to him," Salter said.
McCain and Salter were already working on their seventh book together which instantly took a reflective turn.
"He wanted it to be more personal and to convey just how fortunate he believed he was for being able to serve this country for 60 years," Salter explained.
The result: "The Restless Wave."
This new book allows McCain to tie up some loose ends, publicly admitting for the first time that during his 2008 presidential run, Joe Lieberman was his first choice for his running mate.
"(McCain’s) aides, among them myself, had persuaded him that it wouldn't be possible," Salter said.
They told McCain putting a Democrat turned independent on a Republican presidential ticket would spark a convention revolt.
"He wanted to pick Joe Lieberman, but he has never expressed any regret, not privately nor certainly publicly about picking Governor Palin," Salter said.
McCain also explains being approached in 2016 with the now-famous dossier about Donald Trump.
"He went over to see the FBI director at his earliest convenience and delivered it to him and said, 'I assume you will vet this,'" Salter explained.
During his nearly four decades in Congress, McCain sparred with presidents in both parties, but makes clear his concerns about Donald Trump are fundamental, writing:
"The world is learning to live without our active leadership. That's not good for the world and it won't be good for us."
A Vietnam prisoner for five and a half years, brutally tortured for most of it, McCain wants this book to be a guide for standing up for those oppressed around the globe as he's done for decades.
"He goes to Burma and he meets with three guys who had been political prisoners for 20 years, that had just been released from prison, and when he started to speak, one of them just started to cry because he had heard his voice on Radio Free Asia so many times defending them by name," Salter said.
For over 30 years, Salter has helped McCain convey his essence.
"'We were born to love and we were born to have the courage for it. So, be brave. The rest is easy.' I thought that was the most McCain-eque thing he ever said," Salter said.
That, or maybe this - in the final chapter.
"We need each other. We need friends in the world and they need us. The bell tolls for us, my friends," McCain said.
That, of course, is a reference to McCain's favorite book "For Whom the Bell Tolls" by Ernest Hemingway.
And in the last full page of his book, McCain quotes the book directly saying, "The world is a fine place and worth fighting for and I hate very much to leave it."
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