Robert Caro writes, and waits, during the COVID-19 outbreak

NEW YORK — On most days since the coronavirus spread through Manhattan, Robert Caro has held to a familiar routine. He rises early, walks to his office down the street, spends hours on the fifth and final volume of his Lyndon Johnson biography and enjoys a late-day stroll in Central Park with his wife, Ina, both of them wearing protective masks.

“The park is sort of beautiful without people in it,” he said during a recent telephone interview with The Associated Press.

The 84-year-old Caro jokes that he has a long history, like many writers, of social distancing. But the pandemic has touched him personally and professionally. A close friend, the author and actress Patricia Bosworth, died last month from the virus. Spring is usually a prime season in New York for literary events, but all have been cancelled and the Caros are staying in their apartment when possible, letting one of their children bring them groceries.

The historian had been hoping to visit Vietnam in March as part of his research for his Johnson book, but postponed the trip. He needs to looks through some papers in the Johnson presidential library in Austin, Texas, but is resigned to waiting indefinitely. “That's a great frustration," he acknowledged.

Meanwhile, he is so immersed in one section of the last Johnson volume, set during 1967, that he is not leaving for his more rural and presumably safer home on Long Island until he's done. The section, he says, “is as long as many books,” a description his many readers would find easy to believe.

Caro began the Johnson books in the mid-1970s, around the time he turned 40. He has completed four volumes, totalling more than 3,000 pages, and has outlived many of his key sources. He was loathed by some Johnson loyalists for his second book in the series, “Means of Ascent,” which presented Johnson as a boorish man and a singularly ruthless and unprincipled politician. But the mood shifted after Vol. III, “Master of the Senate,” published in 2002 and a defining chronicle of Johnson's legislative genius that politicians today still study.

His most recent book, “The Passage of Power,” came out eight years ago this month. Its story ended in mid-1964, with Johnson on the verge of passing an extraordinary run of legislation that had many celebrating him as a fulfiller — and even exceeder — of the hopes and vision of the assassinated John F. Kennedy.

But by 1967, when Joan Didion wrote “the centre was not holding," the country and Johnson's presidency were unraveling. Riots devastated Detroit and Newark, New Jersey, among other cities; hundreds of thousands of troops were in Vietnam; inflation was taking hold and Congress was resisting continued funding for his Great Society domestic programs.

“He's in a moment of crisis," Caro says. “I’m trying to show in this section of this book what it's like to be president of the United States when everything is going wrong.”

According to Caro's publisher, Alfred A. Knopf, no book receives more inquiries about its completion than the last Johnson volume, even though anyone with a long memory, a love for history or access to Wikipedia knows how his life turns out. The escalation of the Vietnam War, and the failure to win in it or reach a negotiated settlement, drove Johnson to announce in March 1968 that he would not seek re-election. He lived just four years after leaving the White House, dying of a heart attack in January 1973, at age 64.

"As great as his (Caro's) earlier books have been, this is the culmination, the one many of us have been waiting for," the journalist-historian David Maraniss, whose books include a prize-winning work on 1967, “They Marched Into Sunlight,” wrote in an email to the AP. "Everything that came before leads to these years, all of LBJ’s work and all of Caro’s amazing reconstruction and assessment, when the world explodes at home and overseas and Johnson struggles with his powers, his beliefs, and his soul.

The highlight's of Johnson's career are well chronicled, but Caro's books stand out for the moments when he pauses the narrative and explores in depth how government works — whether the passage of the 1957 Civil Rights Bills that Johnson shepherded while Senate Majority Leader, or his first days as president, when Kennedy's death instantaneously transformed Johnson from a depressed and endangered vice-president to the world's most powerful man.

“Bob has an unusually devoted following among readers because he has a powerful narrative voice that lends high drama to everything that he describes," fellow historian Ron Chernow wrote in an email to the AP. "Those who don’t read biography imagine that great length is a deterrent. But genuine readers of biography crave stories on an epic scale and that Bob always delivers reliably and brilliantly.”

In the new book, Caro plans a takeout on what it was like to be elderly before the passage, in 1965, of Medicare. Talking about his section on 1967, he explains that Johnson had once been confident that the country could fight wars both home and abroad — defeat the North Vietnamese overseas and conquer poverty in the United States.

By 1967, “he's found out that he's wrong, although he doesn’t admit that he's wrong,” Caro said.

When asked, inevitably, how soon he will be done with Vol. 5, Caro declines to say directly and give what he calls his standard answer: “It doesn't matter how long a book takes, what matters is how long a book lasts." He has received virtually every literary prize, but he savors more private and unexpected tributes, like seeing a young person carrying a copy of one of his books. He then speaks of a recent letter, sent to his literary agent by the fiancee of a judge dying of cancer, that compelled him to respond.

“The fiancee wrote this beautiful letter, saying that my books meant a great deal to him, and that a letter would mean a lot to him,” Caro says. “So I spent a couple of hours composing a letter. I try to answer handwritten letters and I've been getting more of them since the pandemic. I used to get mostly emails. Handwritten letters had almost stopped.”

Hillel Italie, The Associated Press