We're meeting for a column called Lunch With… but my appointment with Kerry O'Brien is scheduled for 8am. It was the only time he was free. At 70, and five years after he nominally "retired" from his full-time role as host of the ABC's 7.30 Report, O'Brien is a busy man.

He's on a national tour to promote his book Keating, which was two years in the making and is a companion piece to, and extension of, the four-part series on the former Labor prime minister that aired on ABC-TV to great fanfare in 2013. O'Brien conducted 16 hours of interviews with Keating for the TV series, and says he's topped it up with that much again, all of the sessions conducted in Keating's Sydney office, with his hand-annotated press clippings from 30 years in public life close at hand.

That's a long time to spend chatting with one person I say as O'Brien – dressed casually in jeans and thick sweater, not a green pen in sight – orders a strong coffee. Would you say you and the ex-PM have become friends?

"I think there were moments where there was a real sense of friendship. There is a closeness in the process – and if there wasn't, I would have been worried because it would have meant we just weren't connecting with each other."

Whatever amity exists, it's predicated more on a shared interest in the serious stuff of life – politics and policy, the getting and holding of power – than on talking footy over beers and pies at the local. As our breakfasts arrive – poached eggs for him, a mushroom and gruyere omelette for me, both with thick rashers of excellent bacon (the staff at Pei Modern call it "steakon") – O'Brien tells me he first met Keating in 1987, when he moved to Canberra for the ABC.

Early on in his tenure he popped into the then treasurer's office to introduce himself. "I said, 'I'm not looking for cheap tips but I would appreciate the opportunity to drop by occasionally and talk on a background basis to get a better understanding of issues, what's going on'. And he said he did that with very few people but he would do it with me because he knew I took the whole spectrum of politics seriously, including policy."

That's a fair summation of the book: it's no kiss-and-tell revelatory exercise, but rather a series of sober and relatively high-minded conversations about Keating's life, his rise through the Labor ranks, and his absolute commitment to the idea that governing effectively is about having good policy, not merely playing politics.

There is one other thing they have in common, though: a working-class Catholic upbringing. In truth, neither quite fits the stereotype of "working class". Keating's father started as a boilermaker but ended up running a company that employed 100 workers. O'Brien's father was a university-educated hospital administrator, who moved his family around Queensland for work.

Still, class has as much to do with self-identity as it does with socio-economic circumstances and, O'Brien says, "we were certainly working-class in our heads".

His great-grandfather arrived in Australia as a refugee from the Irish potato famine in 1851, "and within four generations they went from unskilled farm labourer to a Harvard PhD – my brother. That is the one great recurring story with people finding their way out of poverty, is education."

His grandfather was a grocer, a "humble man" whose great boast in life was that he was never out of work during the Depression. O'Brien's  father didn't buy his first car until he was 51. "I was 12 when we moved into our first house with my parents' names on the title deeds," he adds. "He was very cautious with his finances because he too had been raised in the Depression."

Young Kerry grew up hearing stories of people roaming the countryside looking for work or a feed, and of the people who either turned them away or offered help, despite being little better off themselves. Formative stories, about "the good and the bad of human nature", he says.

At school in Brisbane, he spent nine years fighting with the Christian brothers who taught him. "Let me guess," I say. "You asked too many questions?"

"They found me an extreme irritant in the classroom," he says, with a throaty laugh that we didn't hear enough of on the telly. "I remember asking a missionary priest, 'Are you saying we can't question the existence of God?' And he said, 'The greatest sin in the eyes of God is the sin of intellectual arrogance'.

"I went away and pondered that and I think it was the beginning of the end, though it took a while."

He was in his late 20s before he was ready to admit he no longer believed, a view also reached by his older brother, who had gone away to become a Christian brother at the age of 14.

"But I don't regret for a minute the Catholic upbringing that I had," he says. "I might regret some of the hidden damage of nine years of being belted by the brothers, but I don't regret the Catholic culture I was exposed to in terms of social justice and basic fairness, that sense of all people being born equal.

"Keating's line on it – and this was a part of the rapport or understanding between us – was that we all come into this life the same, we all go out of it the same. I do believe the single greatest aspiration of any community should be an aspiration of fundamental fairness."

For all that he found common ground and some sort of connection with Keating, O'Brien is at pains to point out that "I haven't done this to promote Paul Keating. I'm not an advocate of Paul Keating. I hope that the flaws in the man – the flaws in the glass, as Patrick White said – are evident." 

Even though he was starting with a rich vein of material he already knew, and most of the words were coming from his subject, O'Brien concedes he found writing the book surprisingly difficult.

"I'd sit down and keep finding reasons to get up," he says. "It drove my wife [former Sydney Morning Herald radio columnist Sue Javes] mad. I'd wander into her office just down the corridor. By the end she didn't need the arrow pointing back out the door – there was a certain look that said 'Why are you here?'"

He carried Keating around in his head for a very long time. So long, in fact, that when Javes found herself sitting next to Keating and his former wife Annita at the memorial service for Gough Whitlam (O'Brien, who was Whitlam's press secretary in 1977, was MC), she told them, "Now I know what Princess Diana meant when she said there were three people in this marriage".

It wasn't meant to be so all-consuming. When O'Brien announced his retirement from the 7.30 Report in 2010, his intention was to spend more time getting to know his family (he has six children, from two marriages). Within weeks of leaving the hosting chair, though, he had signed on to host Four Corners – a less demanding job, for sure, but one that still requires he travel from his couple of acres by the creek in northern NSW  to Sydney 43 times a year.

Soon he was stuffing the calendar with speaking engagements, flying in and out of his rural paradise three or four times a week. "And suddenly I've got a bloody whiteboard", he says, chortling, and still a little horrified, at the memory.

In retrospect, he says, "retirement was possibly the wrong word". But after all those years covering politics, "7.30 had just become Groundhog Day for me".

Do you miss the cut and thrust at all? "No I don't. I'd come to the end of my time. It got to the point where I was pushing myself to get out the door and to the office. Though once I was there I would still get caught up in it."

Having taken 70 years to write his first book, he's not tempted to rush into a second, though he does have something in mind. He's not willing to divulge much about it, though, other than to say, "It won't be about another person".

Do you have a novel in you? "No," he scoffs. "In another life there might have been, but it wouldn't have been Proust."

Would it have been Harold Robbins? "No, it wouldn't have been Harold Robbins either," he says with a laugh, "although he was actually a neighbour of ours in Los Angeles when I went over there for the Seven network."

The trashy novelist was on one side, Elton John was across the street, Cary Grant was up the road: O'Brien isn't averse to dropping a few names. It's not all politics in his world after all.

When I ask him to nominate his favourite interview subject he demurs, saying (quite fairly) there are too many to choose from. But then he settles on a few names that suggest while he might not have been Marcel Proust in another life he just might have been Michael Parkinson.

There was Neil Young, who turned from surly to forthcoming when he realised O'Brien  had done his research and knew his music; James Taylor, who was as ready and willing to talk about his years in the drug-addled wilderness as his minders were determined to prevent him; and Bette Midler, who appears to have charmed the green pen right out of O'Brien's fingers.

"We had this odd little bubble in time where she and I sat down amid her endless retinue of people and we talked for about 20 minutes before we started the interview, just about Australia and Australian politics and American politics," he says. "Then we did the interview and talked for another 20 minutes before they hogtied her and dragged her away.

"And I thought at the time how nice it would be to say to Bette Midler, 'You're obviously interested in this country, would you like me to throw together a dinner party with eight people you might find interesting to talk to?' And of course I bit my lip and didn't."

You can just imagine the scene. Would Keating have been there too, I wonder. Robert Hughes, perhaps? Germaine Greer?

Do you regret not asking her?

"I do regret it," he says, before conceding it was inevitable he wouldn't. "As a journalist I've never had the assumption that I'm part of the story, and I've always had a reluctance to insert myself into it."

He's old-school, Kerry O'Brien. May he live long and prosper.

Keating, by Kerry O'Brien, is published by Allen & Unwin, $49.99. Follow Karl Quinn on Facebook: karl quinn writer
On twitter: @karlkwin

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