But historian Joyce Appleby, professor emerita at the University of California in Los Angeles, predicts that future generations will find things to puzzle over, even if 9/11 "isn't connected to a great story like the Civil War or a great person like Lincoln.
"It was an attack on a whole range of values in America," she says. "Here were two buildings that represented modernity, success, power. Then you have those pictures. They're going to be powerful for a long time."
Indeed, images are crucial to three of the most talked-about and top-selling 9/11 books:
Aftermath: World Trade Center Archive, by Joel Meyerowitz: This stunning (and pricey, at $75) coffee-table book has won widespread praise for its photos of the wreckage left by the World Trade Center attacks and the ensuing cleanup effort. Mr. Meyerowitz's grand images reveal the eerie beauty of toppled and wounded buildings, dwarfing the workers looking for victims' remains. His nine-month stint at ground zero almost didn't come to pass because of bureaucratic snarls. But charm and moxie took him and his wooden camera past the barriers into a strange world where "I cried with men on the site almost every day," Meyerowitz writes.
Watching the World Change: The Stories Behind the Images of 9/11, by David Friend: Hundreds of professional and amateur photographers preserved 9/11 on film. The Associated Press alone distributed 1,700 frames in the 18 hours after the attacks.
Mr. Friend, an editor at Vanity Fair magazine and former director of photography at Life magazine, offers a fascinating day-by-day account of how both still photographers and television cameramen flew into action over seven days.
Friend explores how 9/11 reflected – and brought about – changes in the technology of photography. And he carefully mixes the stories behind the images in the book – both famous and obscure – with perceptive commentary on their power to dispense "ripples of compassion, sorrow and valor."