In the introduction to a collection of essays on the terrorist attacks of Sept. 11, the scholars Strobe Talbott and Nayan Chanda write that their working premise was "that the unforgivable is not necessarily incomprehensible or inexplicable."

A similar conviction animates many of the books being published around or after the anniversary of last year's terrorist attacks, an outpouring that Publishers Weekly estimates to be as high as 65 to 150 titles, and that comes in the wake of dozens of books on the subject already published in the last year.

They are books that run the gamut from historical examinations of the roots of today's terrorism ("Militant Islam Reaches America" by Daniel Pipes) to picture books about quilts inspired by the World Trade Center ("America From the Heart," edited by Karey Bresenhan); from closely observed accounts of the recovery effort at ground zero ("American Ground: Unbuilding the World Trade Center" by William Langewiesche) to eclectic meditations on the future of civil liberties in the post-9/11 world ("It's a Free Country," edited by Danny Goldberg, Victor Goldberg and Robert Greenwald).

There are books about the victims, the rescue workers, the survivors and the terrorists; books about American intelligence failures and the heroism of the New York City Fire Department. There are books about how comic-book writers, college ministers, broadcast journalists, writers of young-adult literature, West Coast authors, feminists and child artists responded to that day. And there are books exploring the political, religious, psychological, technological and environmental consequences of the terrorist attacks. Many major news organizations have brought out books about Sept. 11; in the case of The New York Times, two books by the newspaper's reporters and photographers are being published, as well as at least four other books by individual staff members.

At Barnes & Noble bookstores in New York, tables are stacked high with titles related to 9/11, a grouping that includes not just books about Sept. 11, but also picture-book tributes to the World Trade Center, poetry anthologies about New York, coffee-table books about the American flag and stocking-stuffer-type books on the inspirational words of former Mayor Rudolph W. Giuliani. Some of the books being published this fall have a bizarre keepsake quality to them — CBS News's "What We Saw" comes with a DVD of the network's news coverage of the day — and some, like Philippe Petit's account of his 1974 high-wire walk between the towers ("To Reach the Clouds"), have only the most tangential connection to the events of Sept. 11.

This flood of books raises important questions about how we remember the past: What is the line between preserving our historical memory — ensuring that "we will never forget," as the banner erected over ground zero pledged — and cashing in on a terrible event, between remembering and exploiting the dead? Does reading about (or viewing pictures of) that September day reopen old wounds, or help us come to terms with our loss?

The books illuminate how our self-absorbed, therapy-minded and information-overloaded society tries to process a national tragedy. They remind us that journalists are often spurred to do their best work in the shadow of others' misfortunes. And they point up our culture's penchant for merchandising every aspect of our lives, including, maybe even emphasizing, what we hold sacred.

Many 9/11 books also ratify the popular Oprah-esque belief that talking or writing about a devastating event can somehow exorcise our demons. The proliferation of cheesy self-help titles about coping with the emotional aftermath of 9/11 — like "Live Aware, Not in Fear: The 411 on 9-11" or "Chicken Soup for the Soul of America" — go so far as to suggest that people can cope with Sept. 11 the same way they try to cope with an unfaithful spouse or a dysfunctional childhood. "The September 11 Syndrome: Anxious Days and Sleepless Nights" suggests that there are "Seven Steps to Getting a Grip in Uncertain Times," while "The Deeper Wound" by Deepak Chopra offers 100 affirmations for beginning "the healing process," like "I will appreciate myself, including my pain."

At the same time many of the more serious 9/11 books try to subject the chaos and fear of that seismic day to the ordering, sense-making mechanics of narrative. In compressing a mass of incidents, images and evidence — material already familiar to us from the media coverage the events received (in sharp contrast to the attack on Pearl Harbor, which did not immediately interrupt regular programming on many radio stations) — many books create story lines that play to the public's perceived need for closure. These books consciously or unconsciously accentuate the positive, following a therapeutic arc that underscores the nation's movement from shock and horror, through grief and mourning, toward patriotic solidarity and resolve, never mind that Osama bin Laden has yet to be found, Al Qaeda remains a threat, and the war on terrorism rumbles on with no end in sight.

In the days and weeks following the destruction of the World Trade Towers, small shrines, filled with homemade tributes to the victims, sprang up around New York City, and the Internet was engulfed in postings by people eager to communicate their reactions.

Such grass-roots expressions of shock and grief have now been turned into books. For instance, "The September 11 Photo Project," edited by Michael Feldschuh, and "Here Is New York: A Democracy of Photographs," conceived and organized by Alice Rose George, Gilles Peress, Michael Shulan and Charles Traub, both grew out of unusual New York photography exhibits that were open to contributions from the public, and the images in their pages — some, classic works of photojournalism; some, more personal tributes to the dead — create a choral portrait of 9/11 and its echoing emotional fallout.

Like the images of that day taken by professional photographers — which can be found in volumes like Reuters's "September 11: A Testimony," the Magnum photographers' "New York September 11" and "Above Hallowed Ground" by the photographers of the New York City Police Department — they give us history unadorned in a succession of freeze frames. Whereas many writers strain to find words to describe the unimaginable, these images possess a stark and simple eloquence: glimpses of what was before, during and after, caught and preserved in the click of a shutter.

Such works of photography are firsthand pieces of testimony, and like the many memoirs, biographies and news accounts being published, they form the first wave of work about 9/11, work that lays the foundation for later writers. As literature about the Holocaust, Hiroshima and the AIDS crisis attest, books about large historical traumas tend to follow a recognizable trajectory: eyewitness reports and autobiographical accounts by survivors, giving way to documentaries and later, fictional treatments that tend to grow more stylized and metaphorical with the passage of time.

Only a year after 9/11, however, the dangers of aestheticizing or selfishly appropriating an atrocity, still raw and terrible in our minds, remain great: it will be a long time before the events of Sept. 11 can be absorbed by our collective imagination and a long time before they can be assimilated into our fiction.

Given our impatient fast-forward culture, however, a floodlet of books about artistic responses to 9/11 has already begun to appear, including "Poetry After 9/11," several collections of work by comic-book artists ("9-11: Artists Respond" and "9-11: Emergency Relief") and multiple anthologies of miscellaneous writings (most notably, "September 11, 2001: American Writers Respond," "Afterwords: Stories and Reports From 9/11 and Beyond," "110 Stories: New York Writes After September 11" and "Before & After: Stories From New York").

Not unexpectedly, the most powerful pieces in these volumes tend to be documentary in tone and effect, chronicling what a writer saw or felt that day in plain-spoken language. The more writerly submissions — like one in which Erica Jong talks about September days in New York where "the sky is blue as Alice in Wonderland's Victorian pinafore" — feel overly self-conscious, emphasizing style over content, sensibility over testimony.

Some accounts about visiting Ground Zero or hanging out with firemen have a noxious, self-dramatizing quality; you can feel the self-congratulatory frisson the authors are experiencing at the thought that they are witnessing history firsthand. Equally toxic are the accounts that try to turn the events of 9/11 into a mirror of the writer's own narcissism.

Elizabeth Swados, for instance, who was involved in a production of Shakespeare's "Merchant of Venice" in Paris at the time, writes, "I have this uneasy kind of magically inspired guilt that maybe September would've been different if I hadn't been involved, as a Jew, in such a blatantly anti-Semitic play."

Meanwhile, in anthologies like "How Did This Happen?," edited by James F. Hoge Jr. and Gideon Rose, and "The Age of Terror," edited by Strobe Talbott and Nayan Chanda, scholars have begun to try to situate this seemingly anomalous event in a historical and political context, attempting to make the enormity of what happened that day somehow understandable.

Several new books — including "The Cell: Inside the 9/11 Plot, and Why the F.B.I. and C.I.A. Failed to Stop It," by John Miller and Michael Stone with Chris Mitchell; "The Age of Sacred Terror," by Daniel Benjamin and Steven Simon; and "Breakdown," by Bill Gertz — examine the failures on the part of the American government to anticipate the terrorist attacks, and a forthcoming book by Bob Woodward, "The Nation at War," will take a behind-the-scenes look at the administration's response to 9/11 and its war on terror.

Books on the larger historical ramifications of 9/11, however, will continue to appear for many years to come. Even now, four decades after the assassination of President John F. Kennedy, scholars continue to debate whether Lee Harvey Oswald acted alone; and six decades after Pearl Harbor, they continue to debate the nation's lack of preparedness for that surprise attack.

We are still in the midst of seeing how the events of Sept. 11 changed America at home and altered its role in the world, and it will take further time and distance to situate these unfurling developments in some kind of historical perspective. As Kierkegaard once observed, "Life must be lived forward, but understood backward."