Robert Hicks is the author of the novels “The Widow of the South” and “A Separate Country.”

FRANKLIN, Tenn. — IN his 1948 novel “Intruder in the Dust,” William Faulkner described the timeless importance of the Battle of Gettysburg in Southern memory, and in particular the moments before the disastrous Pickett’s Charge on July 3, 1863, which sealed Gen. Robert E. Lee’s defeat. “For every Southern boy fourteen years old,” he wrote, “there is the instant when it’s still not yet two o’clock on that July afternoon.”

That wasn’t quite true at the time — as the humorist Roy Blount Jr. reminds us, black Southern boys of the 1940s probably had a different take on the battle. But today, how many boys anywhere wax nostalgic about the Civil War? For the most part, the world in which Faulkner lived, when the Civil War and its consequences still shaped the American consciousness, has faded away.

Which raises an important question this week, as we move through the three-day sesquicentennial of Gettysburg: does the Civil War still matter as anything more than long-ago history?...