In Cronkite, his hefty new biography, author and historian Douglas Brinkley tackles the “most trusted man in America,” as newsman Walter Cronkite was known for decades. Cronkite, born in Missouri in 1916, cut his teeth as a World War II wire-service reporter and was anchor of the CBS Evening News from 1962 to 1981. Millions of viewers watched him report, eyes glistening, the assassination of JFK; cheer on the space program (with tinker-toy like props on his desk); and reproach Lyndon Johnson for turning Vietnam into a bloody stalemate. (“If I’ve lost Cronkite, I’ve lost the country,” LBJ supposedly said to an aide after a damning CBS News special report on the war in early 1968.)

Brinkley’s treatment is generally sympathetic but at the same time demythologizing. His Cronkite is rendered, in human scale, as a figure of enormous ability and core integrity (with a few lapses) but also colossal ambition and decided political opinions. And as Brinkley shared with me in a wide-ranging telephone interview, Cronkite, who died in 2009 at age 92, had a canny sense of his invaluable “most trusted man” brand. Excerpts from the conversation follow:

Paul Starobin: The popular image of Cronkite remains as a kind of favorite uncle welcomed into the American household. But that wasn’t really his personality, right?

Douglas Brinkley: There was nothing avuncular about Walter Cronkite. You don’t make it to the top of the profession and stay there decade after decade by being weak-kneed. It is a slaughterhouse of an industry. Cronkite clings to air time as much as possible. If he smells you nipping at his heels, you’ll get whacked, you’ll disappear. If you poached on his turf, or if you tried to take him down a few notches, you were met with wolverine fierceness. Walter Cronkite is the single most competitive person I have ever written about—ranging from Henry Ford, Theodore Roosevelt, and FDR to John F. Kennedy.

Paul Starobin: A prime example of that in the book is Cronkite’s defiant response to an attempted smackdown by CBS founder and chief William Paley. After Paley decreed that Cronkite would not anchor the 1964 Democratic national convention in Atlantic City, Cronkite moved the CBS Evening News from New York to that city to broadcast the regular show from there. “Retreat was not an option,” you write. Where did that competitive drive come from?

DB: He grew up in the Depression, the family had no money, he was the child of an alcoholic father, he had been fired a lot in his life, he clung to his jobs. His fierce competitiveness is wonderful, but his inability to accept a defeat in trivial things [like card games] is a quirk, as is his extreme cheapness—not leaving tips, never picking up the tab.

PS: I’m struck that you see parallels between Cronkite and Ronald Reagan—perhaps not the likeliest of pairings.

DB: There were very many similarities between Ronald Reagan and Walter Cronkite as personalities. Both were from the Midwest, both had alcoholic fathers, both had to make up sports coverage [as offsite radio broadcasters, riffing off wire-service accounts of the games], both had to disarm people with charm. Both wore well with people, and both are beloved in America.

PS: Did he deserve the “most trusted man in America” moniker?

DB: What a TV network decides to run as news—by nature it has some form of bias. Cronkite pushed for civil rights, the environment, women’s rights. He made a decision that Watergate was a real big story. I ended up believing that he was a journalist to trust, but he was also part and parcel of his times.

PS: What about his role as a cheerleader for NASA and the space program?

DB: On NASA boosterism, he is either praised or guilty as charged. He was seeing it as a big special-event story. So the question is whether he is right to be focusing on space and pushing that story narrative. I feel [the answer is] yes.

Paul Starobin , a former Moscow bureau chief of Business Week, is the author of After America: Narratives for the Next Global Age.