Simeon Booker speaks at podium at his retirement party. (Hamil R. Harris/The Washington Post)

The great Simeon Booker, one of the bravest journalists of our time, faced dangers far worse than a petulant president’s social media feed. Booker refused to be cowed — and ultimately helped change the nation. His life’s work should be a lesson to us all about the power of truth to vanquish evil.

Booker died Sunday at 99. At the height of his career, few could have imagined he would live so long.

As Washington bureau chief for Chicago-based Johnson Publications, publisher of the newsweekly Jet and the monthly magazine Ebony, Booker went to the Deep South to cover the most tumultuous events of the civil rights movement — life-threatening work for an African American journalist.

In 1961, he accompanied the Freedom Riders on a bus journey from Washington to New Orleans, testing whether Southern states would comply with a federal mandate against segregated interstate travel. In Alabama, the protesters were firebombed once and beaten twice by white mobs before federal officials, acting on orders from attorney general Robert F. Kennedy, flew them to safety.

Booker covered the seminal 1965 march from Selma to Montgomery. He was there when Alabama state troopers savagely attacked demonstrators with billy clubs and police dogs — images that shocked the nation and helped shift public opinion outside of the South from indifference to outrage.

As The Post reported in its obituary, Booker returned many times to the South to report on the struggle: “For his safety, he sometimes posed as a minister, carrying a Bible under his arm. Other times, he discarded his usual suit and bow tie for overalls to look the part of a sharecropper. Once, in an incident retold when Mr. Booker was inducted into the National Association of Black Journalists’ Hall of Fame in 2013, he escaped a mob by riding in the back of a hearse.”

Booker was The Post’s first full-time black reporter, hired by publisher Philip Graham, who gave him an admonition similar to the one Brooklyn Dodgers General Manager Branch Rickey had given to Jackie Robinson: “If you can take it, I’m willing to gamble.” Washington was a segregated city in 1952 — Booker recalled that when he went out to cover a robbery, “they thought I was one of the damn holdup men” — and ultimately, he found the work unsatisfying. In 1954, Johnson Publications offered him the bureau chief job, and he took it. He kept it for five decades.

Booker is best known for the story he wrote for Jet about Emmett Till, the Chicago teenager brutally slain in Mississippi in 1955 for allegedly whistling at a white woman. In Chicago at the time, Booker tracked down Till’s mother, Mamie Till-Mobley, and was with her when Till’s mutilated body arrived.

Booker wrote: “Her face wet with tears, she leaned over the body, just removed from a rubber bag in a Chicago funeral home, and cried out, ‘Darling, you have not died in vain. Your life has been sacrificed for something.’ ”

Jet photographer David Jackson took photographs of Till’s brutalized body that remain among the most searing and indelible images of the century.

Booker’s death comes at a moment when journalism and the civic necessity it seeks to provide — truth — are under assault. President Trump and his amen chorus are cynically trying to delegitimize news organizations whose work they find inconvenient. They seek to deny the existence of objective, ascertainable fact. Trump goes so far as to use his Twitter feed, with its millions of followers, to attack individual reporters and demand they be fired.

Journalism’s response must be to tell the president — politely, with all due respect to the office — to stuff it.

There are facts. There is truth. We try our best to get everything right, but of course we sometimes make errors. When we do, we must correct them promptly and fully — and move on. The only “fake news” is the self-serving rubbish Trump tries to peddle through insistent repetition. No matter how often he lies, it is our job to call him on his lying. Every single time.

One of the media’s most important roles in our democracy is to hold public officials accountable, and if they don’t like it, too bad. When they lash out at us viciously and unfairly, as Trump so often does, we should remember all the brave journalists who have faced much worse.

More than once, Simeon Booker had to escape from Southern towns where white vigilante mobs were on the prowl to “get that man from Jet.” We should be able to withstand a few nasty tweets.

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