The Jim Crow era of our nation isn’t ancient history. Today, I learned the Emmett Till murder case is still open — and, apparently, some key players are still alive.

I know this now because of some white Ole Miss students who posed with a memorial to Till … brandishing guns and smiling.

Emmett, who was 14 when he was killed in 1955, would have turned 78 on Thursday. The sign, which has been replaced multiple times after being vandalized, marks the spot along the Tallahatchie River where Emmett’s body was found after he was tortured and lynched. He had been accused of whistling at a white woman behind the counter of the grocery store where he went to buy candy. Last year, the cold case was quietly reopened by the Justice Department after the woman recanted parts of her story.

Emmett’s family said on Thursday that their resolve was even stronger after the episode.

“This is still an open murder case,” Ms. Watts said. “Damaging that sign is not going to deter me or other members of our family that are continuing to pursue justice.”

The past isn’t dead. It’s not even past.