In a new book, "A Different Drummer: My Thirty Years With Ronald Reagan," Deaver, who was Reagan's deputy chief of staff from 1981 to 1985, uses anecdotes to reveal Reagan's personal habits - painting a gleaming portrait of the former president.
"I think what made him tick was duty," Deaver told CBS News White House Correspondent John Roberts. "I think first of all, he believes in destiny, and he believed there was a destiny for him, that there was a purpose for him. And that purpose increasingly became, in the last 20 years, to get the Soviets to the table to end the nuclear war.
"I think Reagan's strongest asset was that he knew exactly who he was," Deaver said. "There wasn't ever any question about him. He didn't have to say, 'Well, if I do it on one hand, this'll happen. If I do it this way, that'll happen. Let's go down the middle.' It just was never that way with Reagan."
Deaver said that after the attempt on his life in 1981, Mr. Reagan became even more focused on his personal goal of ending the Cold War.
Ronald Reagan was a master political performer, but were famous moments like "There you go again" the product of a former actor delivering great lines written by others or due to Mr. Reagan's own political savvy? Deaver maintains they were pure Reagan.
"He knew that 'Mr. Gorbachev, tear down this wall' was something that a lot of people tried to take out of the [text of the] speech," Deaver said. "And Reagan, ultimately at the end said, 'I think I'm the President. It's gonna stay in the speech.'"
One of the most controversial episodes in the Reagan administration is the Iran-Contra affair the illegal secret plan for the U.S. to sell arms to Iran and use the money to aid the Contra rebels in Nicaragua. The question has always been how much President Reagan himself knew about it.
Does Deaver believe that Reagan really was out of the loop?
"I asked him if he knew about...the trade...[and he said] he said, 'No. I never did.' And it was the two of us sitting together in the residence upstairs, so I have to believe that."
Since announcing thahe suffered from Alzheimer's disease seven years ago, Ronald Reagan has lived mostly in private, cared for by his wife Nancy.
Deaver acknowledges the tragedy of a man known as the "Great Communicator" losing his eloquence to the cruelty of Alzheimer's disease.
"It's a cruel end, to see someone who was so vital and interested in issues and enjoyed people," Deaver told Roberts. "I think it's so cruel for the family, for Nancy. I mean, there's no way to share all of those memories. I mean, they're only hers now."
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