David Shribman is the former executive editor of the Pittsburgh Post Gazette.

The ascendancy of Donald Trump signaled the end of an era for the Republican Party and, more broadly, for American politics. The eclipse of network television and the advent of streaming services stand as the end of an era for American home entertainment. But in recent days, another era has ended in another realm of American life and culture. There is no turning back from this one, no plausible argument about its significance.

Bill Walton. Jerry West. Willie Mays. The end of an era.

Contemporary life offers us Shohei Ohtani and Mike Trout in baseball, Connor McDavid and Sidney Crosby in hockey, Jaylen Brown and Jayson Tatum in basketball, and Patrick Mahomes and Christian McCaffrey in football. Now add women’s sport stars Aitana Bonmati of soccer and A’ja Wilson of basketball. Coming on strong: baseball’s Paul Skenes and basketball’s Caitlin Clark.

They’re all superstars. Someday, if newspaper columns still exist, someone at the end of those luminaries’ careers may write an end-of-an-era piece about them. That’s in the future, and it promises sporting richness for us all for the next decade and more.

But Walton, West and Mays: Their deaths in less than a month’s time represent a remarkable, almost unbearable loss for sports, which in our fraught moment is perhaps the only shared experience Americans have. In coming days, the country will witness two old men — born before Walton first bounced a basketball, before West first sunk a fadeaway shot at West Virginia University, before Mays entered the major leagues — engage in a debate about the future. The glow from these three sports stars will shine into a future neither Joe Biden nor Donald Trump can even imagine.

This moment of memorials and memories is evocative of an earlier moment created by an American who, unlike the two on Thursday’s CNN debate stage, will be remembered for his grace, elegance and sense of purpose. It occurred nearly three-quarters of a century ago, in 1962, shortly after West scored 42 points in a game against the St. Louis Hawks, when Walton was playing the baritone horn more than basketball, and on the very day Mays hit a home run and notched two RBIs in a 7-0 triumph against the Chicago Cubs at Candlestick Park.

It was then that President John F. Kennedy summoned Western Hemisphere winners of the Nobel Prize to dinner. He looked out at his guests in the East Room and said, “I think this is the most extraordinary collection of talent, of human knowledge, that has ever been gathered together at the White House, with the possible exception of when Thomas Jefferson dined alone.”

The president noted that at age 32, Jefferson could “calculate an eclipse, survey an estate, tie an artery, plan an edifice, try a cause, break a horse and dance the minuet.” On pretty much any day, Mays could make a remarkable outfield catch, propel a pinpoint throw to the infield, steal one of his 339 base thefts and hit one of his 660 home runs. On any day, Walton could hit more than half his field goal efforts and two-thirds of his free throws. On any day, West could sink 27 points — or make a team-changing alteration in his lineup.

These three dined alone.

They were all period pieces: Mays a representative of the emergence of the Black athlete into mainstream white professional sports; West a symbol of the rise of pro basketball to its current position as a global spectacle; Walton a member of the generation of sports stars who also were social and political activists.

When Dartmouth College awarded honorary degrees at its 2007 commencement, it presented one to the secretary of the Treasury, the music director of the Cincinnati Pops Orchestra, a poet who won the National Book Award and the Pulitzer Prize, the president of the University of Pennsylvania, the founding director of the Smithsonian National Museum of the American Indian, the MacArthur Foundation recipient who was a pioneer in designing new models of health care for Black men in urban areas, and the center fielder for the San Francisco Giants.

Only one of those honorees in black robes was besieged for autographs. One of those seeking a signed baseball was James Wright, president of the college.

The three who passed from life into memory in recent days conferred greatness by association.

Elgin Baylor was an exceptional Los Angeles Laker, but he was rendered even greater by playing strong forward to West’s point guard. Larry Hollyfield was a standout at UCLA, but his career was enhanced by the court presence of Walton, especially on the evening when the “Grateful Red” (an homage to Walton’s loyalty to the Grateful Dead) scored 44 points in the Bruins’ landmark 87-66 NCAA national championship game against Memphis.

And who today would remember Vic Wertz, who had an estimable but not stellar career (four-time All Star with a lifetime batting average of .277), but for his role in what became known as The Catch? That — the over-the-shoulder catch at the Polo Grounds during the 1954 World Series that was the marquee moment of the Giants’ sweep against Cleveland — is one of those episodes in American life where anyone who needs an explanation won’t appreciate the achievement.

Throughout this year’s NBA playoffs, player jerseys sported black bands on their shoulders with the name Walton. Since 1969, the NBA logo has featured the silhouette of West, in motion driving down the court. Today, the San Francisco ballpark where the Giants play bears an evocative address: 24 Willie Mays Plaza.

The three are inscribed in the book of records and sewn into our memories — not so much as emblems of a sweeter time but, for two generations of Americans, perhaps more, as reminders that sports, as Walton’s coach John Wooden taught us, don’t build character so much as they reveal character. These three were characters, to be sure. But above all, they were men of character.

They dined alone.

Should they be dining together tonight, somewhere in a place unknown, the table talk would truly be heavenly. And no doubt they would be serenaded by Jimi Hendrix (who “gave us rainbows”), Janis Joplin (who “took a piece of our hearts”) and Otis Redding (who “brought us all to the dock of a bay”) — for those three from sports, along with those three from music, comprise a hell of a band.