Ron Grossman recently tested the historical knowledge of younger colleagues in the Chicago Tribune’s newsroom with sometimes disastrous results.

I took a quick survey in the newsroom the other day, something between a Rorschach test and a pop quiz, asking younger colleagues to identify an iconic photograph of World War II.

While some instantly recognized the image, others couldn’t quite place it.

“I know I ought to know it,” one co-worker said. “It was in the movie, ‘Flags of Our Fathers.’ ” Some, seeing uniforms, realized it must be a war photo. Maybe Vietnam? One got the era right but the battlefield wrong. She guessed it was D-Day, not, as it was, the raising of the American flag on Iwo Jima.