The author and reporter David Halberstam is having a bit of a moment.

The Washington Post recently published a piece, headlined “the greatest reporter of our time,” marking the tenth anniversary of his death. The New York Times caught Trump adviser Stephen Bannon reading a Halberstam book.

Halberstam’s clash as a young reporter with the Kennedy administration, which I write about in “JFK, Conservative,” foreshadowed President Trump’s battles with the New York Times.

In a strange way, though, the Halberstam who is most relevant at the moment, whose writing most cannily anticipated the current situation, isn’t David. It is, instead, his less famous older brother, Michael J. Halberstam, who died in 1980.

Michael Halberstam was managing editor of the Harvard Crimson before David Halberstam was. As an undergraduate, Michael Halberstam won the Dana Reed Prize for the best piece of writing published in a Harvard student publication. He ended up going to medical school and practicing as a physician. But he also wrote a novel, “The Wanting Of Levine,” that was published in 1978.

“The Wanting of Levine” tells the story of A.L. Levine. He is a person from an outer borough of New York who becomes wealthy through real-estate investments. People like to watch him on television. He is “a salesman in a nation of salesmen, an optimist in a nation of optimists.”

He tapes his phone calls. He has a voracious sex drive — “Here’s to pussy,” he says at one point in the book.

At another point, he says, “I don’t care what the New York Times says.”

He runs for president, even though he’s a bit old for the job, is not a professional politician, and has never been elected to anything before. He observes, “In every other important field you have to have some kind of ability or record or intelligence to get ahead. In politics all you need is a sublime faith in yourself.”

His staff urges him to stick to scripted remarks rather than spontaneous ones.

He explains his success by saying, “Politics is a kind of entertainment, and people want novelty in politics like they want it in anything else. Simultaneously, they want continuity.” As a candidate, Levine is a political unknown, but is “familiar” because people have read about him for years.

He is irritated by a couple he encounters that “despite their belief in the unity of man…despised all Catholics, hated all Southerners…, and feared all parts of the country outside the morning circulation zone of the New York Times.”

When he does finally get elected, he angers environmentalists. He installs a political ally as FBI director.

He’s not a conservative or a liberal or even a pragmatist but more of a “clean slate” — someone whose “strongest conviction was that convictions were dangerous.” He is “a middleman,” “someone who genuinely felt for both sides.”

All this takes place in an atmosphere of tension between America and Mexico, amid American anxiety about competition with Arabs and Chinese in the global economy, and in the context of concern about urban crime and rising anti-Semitism.

What does it say about Donald Trump that the book that captures him best so far is a novel written nearly 40 years ago by a Jewish author imagining the first Jewish president getting elected in 1988?

It’s a question to ponder as President Trump arrives in Israel on his first overseas trip.

Mr. Trump, in Riyadh on Sunday, proclaimed, “We will make decisions based on real-world outcomes — not inflexible ideology. We will be guided by the lessons of experience, not the confines of rigid thinking.” He sounded like Levine.

“The Wanting of Levine” concludes with Levine heading out to his inauguration. It’s a book that captures the Trump campaign much in the way Joe Klein’s “Primary Colors” captured the Clinton campaign. But Halberstam, unlike Klein, wrote his book before any of the events happened.

Michael Halberstam didn’t live long enough to write a sequel imagining how the country or the planet would fare with Levine in office. Even the best fiction is an imperfect guide to reality. Sometimes, even so, it is the best guide we’ve got.