NEW YORK – John Dickerson picked a hell of a time to write a book.

The CBS News correspondent was promoted to host the network’s prestigious Sunday morning show “Face the Nation” just over a year ago.

And during that time, the husband and father of two started a podcast, and then turned that venture into a book about presidential-election history.

He did this all while covering what is surely one of the most remarkable presidential elections in American history.

But looking back into history has not been a distraction or diversion from the present, Dickerson said.

In an interview with Yahoo News about his new book, “Whistlestop,” Dickerson said studying history has sharpened his perspective about current events.

“You see the way in which what’s happening now, the past reflects on it,” said Dickerson. “Each campaign you want to say, ‘What’s new and different relative to the past so I know … how a pattern might be repeated — so I know what’s coming — or what’s different, so I really know what to home in on.’”

Dickerson’s book takes the reader through 19 different accounts of important elections, and there are clear parallels in the book between Republican nominee Donald Trump and former Alabama Gov. George Wallace, who ran demagogic and racist campaigns for president in 1968, 1972 and 1976.

“In George Wallace’s 1968 campaign we hear such close echoes of Donald Trump that it’s as if the transcripts have been transposed,” Dickerson writes.

There are also similarities between Trump and Andrew Jackson, the military hero who became the nation’s seventh president.

Thomas Jefferson once expressed alarm at the prospect of a Jackson presidency, telling a friend, “He has had very little respect for laws and constitutions.”

Trump, meanwhile, has shown little understanding of the U.S. Constitution and was called out by the father of a slain U.S. soldier last week at the Democratic convention, Khizr Khan, who pulled out his pocket Constitution and challenged Trump to read the nation’s founding document.

And like Trump, Jackson reveled in the way that the political establishment reviled him. “They will elect me, contrary to their wishes, by their abuse,” Jackson said.

Dickerson, who has interviewed Trump multiple times this year, spent years at Time magazine and at Slate, and has spent much of his career as a writer. A theme in his book is the rise of image over substance with the advent of television.

Now Dickerson enjoys the prestige and visibility of one of TV’s most politically influential shows, but agreed that TV as a medium has weakened voters’ focus on what’s important.

He explained how he has navigated the challenge of interviewing Trump, who constantly changes his own positions, misrepresents or distorts facts, and has taken position and made statements far outside the norms of American politics and governance.

“I feel like … my job is to present the frame as its existed in American history, and be as fair as possible in presenting that: Ask the question, and then people can figure out whether they think Donald Trump is right,” Dickerson said.