NEW YORK - All the news that's fit to print somehow didn't fit in American newspapers before the mid-1950s.

For example, the ugly consequences of Jim Crow culture in the South. Those repressive, segregationist Southern attitudes toward blacks in education, voting, access to public facilities, and almost everything else you could think of.

Not in the New York Times. Not in mainstream white newspapers like The Inquirer. And certainly not in Southern newspapers run by whites.

You might wonder why a journalist with one of the most storied careers in the American newspaper business - chief civil-rights and Vietnam correspondent for the New York Times, executive editor of The Inquirer during an 18-year stretch that garnered 17 Pulitzer Prizes, managing editor of the New York Times during his last active years as an editor - would devote close to 15 years telling the tale of an American press that started out behaving so badly when it came to civil rights.

Simple. Because journalism, an early villain of the piece, turned out to be a hero as well.

"I still to this day think that it's probably the most important domestic story of the 20th century," says Gene Roberts, 74, coauthor with Atlanta Journal-Constitution managing editor for news Hank Klibanoff of The Race Beat: The Press, the Civil Rights Movement, and the Awakening of a Nation (Knopf, $30).

"When you define a story," says Roberts, chatting in his Manhattan apartment filled with the books, art, and mementos of an extraordinary life in journalism, "you're making a judgment - that this is a story. And I think the whole thing we're writing about in the book illustrates that. One year we were saying, as a press, that there's not a story there. And virtually the next year, we were saying there is a story here. And the ramifications of that decision are amazing in their impact."

Determined to tell how the press tossed off its blinders about black life in the South and so opened America's eyes, Roberts started the book himself in the early 1990s, after leaving The Inquirer.

But in 1994, offered a chance to return to the New York Times for a three-year stint as managing editor that would take him to the Times' retirement age of 65, the North Carolina native worried that a book put aside might stay aside.

He brought in as a collaborator Klibanoff, 57, a native Alabamian, who'd not only spent 20 years at The Inquirer, but also worked on three Mississippi papers as a young reporter.

Thirteen years later, they're full coauthors.

"It was his contract, his idea, his inspiration," says Klibanoff. Whereas Roberts started covering the civil rights story that The Race Beat describes in the mid-'60s, Klibanoff acknowledges that he first saw the civil rights movement and its battles from a distinctly younger angle.

"My story," the onetime paperboy says with a chuckle, "is about delivering the Birmingham News, not seeing it on the front page of the paper, trying to figure out how the heck can they keep the story off Page One. . . ."

Both men wrote parts of the book and discussed everything. Klibanoff threw himself into archival research, going after the private papers and letters of Southern editors and reporters. Roberts drew upon what Klibanoff calls his "steel-trap memory."

"He remembers so many things," says Klibanoff. "His memory was 99 percent infallible." Yet, Roberts says, "The deeper we got into it, the more it was clear that it should not be my war stories, it should be a history."

The result - and the reviews - indicate why friends and onlookers who joked for years about why the book took so long aren't joking anymore. Some old journalistic principle about getting it right before getting it done.

David J. Garrow, the Pulitzer Prize-winning biographer of the Rev. Dr. Martin Luther King Jr., deemed it "an important study" in the New York Times. Other reviewers have also been complimentary. Sarah Schweitzer in the Boston Globe judged it "a compelling reminder of the need for a vibrant and free press." Inquirer reviewer Thomas Lipscomb used the magic word "masterpiece," asserting that "there has never been a better study of the importance of a free press."

The Race Beat begins by focusing on Swedish scholar Gunnar Myrdal's classic work An American Dilemma (1944, published with Richard Sterner and Arnold Rose), a portrait of segregation in America. Myrdal astutely judged, as Roberts and Klibanoff relate, that the "future of race relations . . . rested largely in the hands of the American press."

In the 1940s, the authors report, "no major publication had a news bureau in the South," let alone a commitment to cover the region. "In America," they explain, "the First Amendment kept the government in check, but the press, other than black newspapers and a handful of liberal Southern editors, simply didn't recognize racism as a story."

In part, the book, which teems with portraits of everyday journalistic pressures, is the fair-minded chronicle of a generation of Southern journalists and editors, both progressive and segregationist - among them Hodding Carter Jr., James J. Kilpatrick, Ralph McGill - and their struggles over how much to cover, how much to push, how much to resist.

At the same time, Roberts and Klibanoff give ample coverage to the brave black journalists who spurred their white colleagues to better performance.

"These were guys," says Roberts of the white Southern editors, "who were constantly saying or thinking, 'How far can I go without totally cutting off the entire readership?' So they ended up saying I'm a segregationist while advocating change. . . . Hank understood that and I understood that."

By the end of The Race Beat, the crisis year of 1968, much of American journalism had done itself proud. The authors' early explanation that "a small band of liberal white Southern editors would become their region's conscience," is thoroughly and movingly documented.

For Klibanoff, the issues of The Race Beat remain as current as tomorrow's Atlanta Journal-Constitution. He's still covering the "New South" day by day, and the "Old South," whenever it rears its sometimes ugly head.

Today, Klibanoff says, "if you had a small-town weekly newspaper in south Georgia that was saying in print some of the things that some of the newspapers were saying back in the '50s and '60s about black people, it would be a news story. . . . I don't think that anyone who died in 1963 in the South and who came back . . . would be anything but stunned at the changes."

These days, Roberts flies down to the University of Maryland once a week to teach two classes, Civil Rights and the Press, and Writing the Complex Story.

There's a book that students in both those classes should read, but, well, they may have heard about it already.

Contact book critic Carlin Romano at 215-854-5615 or cromano@phillynews.com. Read his recent work at http://go.philly.com/carlinromano.