It hasn’t been easy for Carl Bernstein since he slipped the fold of the Washington Post almost two decades ago, thereby breaking up the most celebrated pair of sleuth reporters in the history of journalism.

For much of the past two decades, Bernstein has pursued an erratic, sometimes invisible course while Bob Woodward, his former partner in Watergate glory, yomped his way through book after book of peerless political scoop-mongering.

Over the years there were frequent reports that Bob and Carl had fallen out, that Bernstein was jealous of his former colleague’s success, that Bernstein’s attempts to write the definitive biography of Hillary Clinton had been paralysed by a bad case of writer’s block. Meanwhile Woodward, still nominally an editor at the Post, was racking up the headlines – and dollars – with a prolific series of insider accounts of life in the Bush White House.

It was Bernstein’s curse, I suggested to him over lunch in Manhattan last week, that he would forever be linked to – and maybe overshadowed by – his former partner in presidential crime.

His fork paused over his salade niçoise. “It’s a pretty good curse to have,” he said mildly, and it soon became clear that whatever their past disagreements, Woodward and Bernstein are once again tight.

His massively researched take on the life of Hillary has taken him eight years to complete, but he insists that writer’s block was not the problem.

“That’s crazy,” he said. “I’ve never had writer’s block in my life. I’ve always procrastinated. It’s only when you’re with Woodward that you work very fast.” Bernstein attributes much of the delay to his struggle to make sense of Hillary’s frequently ambiguous politics, and his efforts to find the right authorial “voice”.

His agonies turned to his advantage. Instead of meeting his original deadline of 2003 – when America’s attention was turned to Iraq – his book has arrived at the perfect moment to catapult him into the most exciting American presidential contest since John Kennedy took on Richard Nixon. It is Bernstein, not Woodward, who will be commanding America’s airwaves in the nonstop discussions of Hillary’s prospects.

In many ways Woodward and Bernstein remain as different as Robert Redford and Dustin Hoffman, who portrayed them so memorably in All the President’s Men, Hollywood’s take on the Watergate investigation. Woodward has become a Washington institution, with a Georgetown mansion to match his

Movieversion:HoffmanasBernsteinandRedfordas Woodward reputation. Bernstein is still the slightly dishevelled New York aesthete, mad about music and the state-of-the-art hi-fi system he has installed in his 27th-floor apartment. Visitors to his cramped study have to be careful not to tread on the $22,000 pair of valve amplifiers that power the massive loudspeakers in the living room next door.

Journalism has made Bernstein rich. He and Woodward recently sold their Watergate notebooks to Texas University for a reported $5m. But he reveals that he nearly didn’t cover Watergate at all.

“I was a part-time rock critic,” he said.

Shortly before Watergate broke he applied to Rolling Stone magazine for a job. “Jann Wenner [the magazine’s owner] was so goddam slow about deciding whether to hire me that Watergate happened and that was that,” said Bernstein. By his own account he wasn’t a very perspicacious rock critic: “I panned Led Zeppelin and that was not a good career move.”

There were sparks when he was first thrown together with Woodward. The methodical reporter and the flamboyant writer argued often about where the story was going. “There was plenty of intellectual conflict, but enormous respect and affection both ways,” Bernstein now remembers.

After Nixon’s fall, cracks began to appear as they became interested in different projects. But Bernstein blames their eventual split on his now ex-wife, Nora Ephron, the writer. “Bob and Nora really despised each other, and to this day are not fans of each other,” said Bernstein. “It made [our partnership] pretty untenable.”

After a year or so without much contact, Bernstein added, Woodward’s marriage “blew up . . . I called him and said, you all right?” Since then they have become each other’s stoutest defenders, and talk “every two or three days”.

With Clinton’s scalp finally under his belt, Bernstein is planning another book and a project in “other media”. He prefers not to be specific, but he acknowledges: “I feel like a free man.”

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