Good morning, it's Thursday, June 21, 2018, the first day of summer. Normally, I write in this space about uplifting events in U.S. history. The underlying idea, I suppose, is to remind ourselves that the hurdles and hostilities we're experiencing have usually been confronted in the past -- often in worse form -- and that we tend to see our way through.

In the arc of the American story, race relations fit that paradigm. But some chapters along that path were so horrific that they remain painful even at a distance. One such episode occurred 54 years ago today when word went out across the country that three young civil rights workers had gone missing in Mississippi.

Michael Schwerner, Andrew Goodman and James Chaney were working on behalf of CORE, the Congress of Racial Equality, one of the organizations leading voter registration drives across the South. They were returning from a trip to see the smoldering ruins of Mt. Zion United Methodist Church, in an unincorporated part of Neshoba County, and were last seen in police custody in Philadelphia, a town with about 5,500 people.

As many as 100 of those residents, including a deputy sheriff, knew where Schwerner, Goodman, and Chaney were -- and that they weren't "missing" at all. They were dead, killed in their early 20s by white racists who kidnapped them, shot them, and hid their corpses with the expectation they'd never be discovered.

But their bodies were found, a grisly discovery that ensured the South would never be the same.

"Freedom Summer," as it came to be known, was officially called the "Mississippi Summer Project." Some 1,000 out-of-state volunteers, most of them white Northerners, supplemented the efforts of the Student Nonviolent Coordinating Committee, a larger corps of Southern black civil rights activists. Their goal was to upend one of the most invidious pillars of segregation: the barriers to African-American voting.

Although these civil rights crusaders were dedicated to nonviolent means of change, the defenders of the status quo were not so constrained. If you think about it, they never had been: At its most basic level, "Jim Crow" -- the American version of apartheid that had taken root in the states of the Old Confederacy -- was enforced by the same brutal tactics that sustained slavery. And in the summer of 1964, the tools of repression used by the Ku Klux Klan in defending segregation included bombings, arson, cross-burnings, and murder.

On June 16, 1964 some two dozen armed Klansmen appeared at Mt. Zion United Methodist Church, which CORE had designated a "Freedom School." The hooded Mississippians seemed to be looking for Mickey Schwerner, who was leading the local voting drive for CORE and who had previously organized a boycott of a white department store in Meridian, a Mississippi town 40 miles away.

Schwerner was at a CORE training session in Ohio, so the mob roughed up several blacks who were present and put the church to the torch. If this was intended to draw Schwerner into the open, it worked. Five days later, he and the two others headed to Mt. Zion -- and into an ambush.

The story of what happened next has been told many times in many venues: how the three civil rights workers were arrested by Neshoba County deputy sheriff Cecil Price, allegedly for speeding; how they were jailed for hours without the opportunity of making a phone call; how Price chased them down after releasing them, catching the trio just before they reached the county line and turned them over to two carloads of Klansmen; how Schwerner, Chaney, and Goodman were shot and buried in an earthen dam at the direction of local Klan leader Edgar Ray Killen; how local and state authorities wouldn't even look into the case; how President Lyndon Johnson directed FBI Director J. Edgar Hoover to investigate; how the FBI opened its first field office in the state of Mississippi days later; how these federal agents helped find the bodies 44 days later, and ultimately found the killers.

Eighteen local white men, including Killen and Price, were indicted on federal charges of violating the civil rights of the slain volunteers. Seven of them were convicted, including Price, but not Killen. Not one served more than six years in prison. None except Killen, that is.

Prodded by Jackson Clarion-Ledger reporter Jerry Mitchell, Mississippi authorities reopened the case in 2004. And on this date in 2005 -- 41 years to the day after the murder of three young men trying to make the world a better place -- Edgar Ray Killen was convicted of the murders in state court by a Neshoba County jury. Earlier this year, he died in prison, where he belonged all along.

The last word shouldn't be about a violent and unrepentant racist, however. Let's have it be about the three brave young men who harbored a dream about the kind of place Mississippi could be.

Michael Henry Schwerner: The Klansmen in Mississippi called him "Goatee" after his wispy chin whiskers, or sometimes just "Jew-boy." But those who knew Schwerner called him "Mickey," and everybody who knew him loved him.

As an 18-year-old student getting ready to enter college, he bought a Volkswagen. He did so for the most sensible of reasons: The car was inexpensive to buy and operate -- and got good gas mileage. But this was 1957, and his mom put to her son a question that any Jewish mother might ask only 12 years after the Nazi death camps were liberated.

"Mickey, are you sure you want to buy a German-made car? You know about Auschwitz and you know that some of your relatives were murdered there. … Are you sure you'll be comfortable driving a Volkswagen?"

This conversation, related in William Bradford Huie's classic book "Three Lives for Mississippi," continued this way: "I know how you feel, Mother. But … I want to spend my life relieving hate, not preserving it. I see reason to hope there will never be another Auschwitz."

That was Mickey Schwerner, who was 24 when he died. The last thing he said to his killers, according to one witness, was, "Sir, I know just how you feel."

James Earl Chaney: What people who knew the Chaney family best remember about James was how he treated his brother Ben. Nine years older than Ben, it was James Chaney who bought Ben his first football uniform, took him for haircuts, and introduced Ben to the very American notion that everyone should vote when they were of age -- regardless of their skin color.

When the teenaged Ben was locked up briefly after accompanying James on a voting drive, it was James who went to the courthouse to bail him out, calling into the cellblock, "Where's my brother?"

"He treated me," Ben recalled after his brother's death at 21, "like I was a hero."

Andrew Goodman: The youngest of the slain CORE workers, Andy Goodman was only 20 when he left this world. He was never able to marry or have children, didn't finish college, and his death left a hole in his family's heart. He did not die in vain, however, which turned out to be his parents' main consolation.

"As a mother, there's nothing worse than losing a son," Carolyn Goodman told the Los Angeles Times on the 25th anniversary of his murder. "There's something about losing a son that's like taking a piece of your life."

Mrs. Goodman then showed the Times reporter a portrait of her boy that was still hanging in his old bedroom.

"I also realize that Andy ennobled my life," she added. "He made me a better person. His death, along with the other two, changed the nation, and made it a better place."