Why do we memorialize Sept. 11?

As you descend into the immense subterranean spaces and through the winding, trauma-saturated displays of the National September 11 Memorial Museum, that question will hardly seem as urgent as it does when you leave, feeling peculiarly uncertain about the answer. But at first, there is nothing to ask: You are submerged in an eerie underworld, haunted by ghostly memories and the murmur of gibbering voices.

Ordinary artifacts are relics of ruin and death here: a Metro Card used by one victim, a lacrosse stick owned by another, shards of World Trade Center window glass, a tattered seatbelt from Flight 77 torn off its mooring. The sounds are television broadcasts and taped messages, secret phone calls from hijacked planes and rescuers on radios wrestling with apocalypse. The voices are those of the unknowing, thinking themselves spared as the first tower is hit; and those of the doomed, knowing they had just seconds for farewells. No wonder the galleries include stands with tissue dispensers.

The power of these exhibits, which chronologically conduct visitors through the day, is unsurpassed in contemporary history museums. And in darkened screening rooms, eyewitness accounts are heard, while locations are pointed out on schematic video sketches of the towers, the Pentagon, or United Airlines Flight 93, the multiple voices masterfully woven into seamless narratives.

So out of remnants and recollections emerges a kind of coherence: the memorial as story. Maybe that is the point. Museums, once repositories of a culture’s sacral visions — temples erected to pay homage to a civilization’s beliefs, collections and creations — have taken on other functions. The approach here almost inverts the traditional model with its timeless aspirations: It creates a museum of experience. It is devoted not to history but to something much more personal and immediate: memory. And in keeping with its devotion to experience, it tries to become an experience itself.

But this emphasis is also strange, because the museum clearly has grand public ambitions. It proclaims its own monumentality. Its scale is so immense that in its cavernous spaces a half-incinerated fire truck looks like a toy. Those ambitions are evident, too, in an epigram from Virgil, its block letters formed from pitted metal salvaged from the ruins: “No Day Shall Erase You From the Memory of Time.”

In this desire for monumental memorialization — and, yes, its failure to achieve it — the museum is not alone. In an interview on its website, the Civil War historian David Blight refers to a “rage in our culture to memorialize,” one unmatched, he suggests, in modern times. One recent book, “Memorial Mania: Public Feeling in America,” by Erika Doss, points out some of the memorials of the last two decades — a Salem Village Witchcraft Victims’ Memorial in Danvers, Mass.; the Oklahoma City National Memorial and Museum; the Astronaut Memorial in Merritt Island, Fla. — memorials to matters great and small, proliferating like identity museums, each staking a claim on public attention.

Add to them memorials mounted around the National Mall in Washington since 1993: the Vietnam Women’s Memorial (1993), the Korean War Memorial (1995), the Franklin Delano Roosevelt Memorial (1997), the World War II Memorial (2004), the Martin Luther King Jr., Memorial (2011), and a proposed memorial for President Dwight D. Eisenhower that was rejected and sent back for revisions after years of planning. Five memorials were completed in the last 20 years; during the preceding 60 years, according to the National Park Service literature, there were three.

This memorial proliferation is also accompanied by flaws, and on the National Mall, they run deep. These memorials can elevate the trivial and undercut the significant; their styles often embrace kitsch, sentimentality or banality. Few suggest what a national or public memorial might be. Most seem designed for current constituencies rather than future citizenry.

A more profound approach emerged from the battlefields of Gettysburg: Despite the freshness of the graves, Lincoln was able to articulate a purpose and meaning that determined the future of a national memorial. Or more recently, the Vietnam Veterans Memorial on the Mall: It brilliantly honors more than 58,000 dead while refraining from glorifying the war itself; it memorializes both with elegant restraint, seeming to speak for the nation as a whole.

But the Sept. 11 museum may be breaking new ground both in its ambition’s scale and the ways it falls short. It is as if by enshrining memory and individual experience, it left little room for more elaborate and public considerations; it doesn’t even try to offer a rough first draft of history.

The museum’s historical exhibition is divided into three major sections. The first chronicles the attacks themselves. The displays are thoroughly permeated by individual experience. So are exhibits of the third part, which chronicles the months that followed the attacks, surveying operations of rescue, search and excavation. Ideas and debates don’t interfere with the determined accumulation of sensations and memories. (I will return to the second part of the exhibition later).

This also affects the approach taken in the museum’s separate memorial exhibition; it is introduced by a plaque referring to the 2,977 killed in that day’s attacks along with six killed in the 1993 terrorist bombing of the World Trade Center. As you enter, you hear a reading of their names. Their faces tile the walls; they are also shown on touch screens, where we can read biographical summaries, accompanied by images and audio. (“My dad was really fun,” one says.) You can also choose to have this information projected in a darkened room. Display cases show us artifacts associated with victims’ lives and hobbies: drumsticks, ballet slippers, a Viking helmet.

The meticulous listing of the dead probably became established in modern memorials with Maya Lin’s Vietnam Veterans Memorial. But at ground zero, who are the dead? They are not primarily emergency workers; few were involved in public service; the vast number have no claim on public attention other than our sympathy. They deserve memorialization within the context of the largest attack on American soil since Pearl Harbor. Yet more attention is given to individuals here than at any other memorial I can recall.

In the plaza, the names are inscribed on the outside of the two memorial pools. Inside the museum, they are again listed, heard aloud, associated with faces and recollections. One reason, surely, is that this is the site of their murder. And the attention to individuality presumably highlights the scale of the terrorist crime.

But the historical exhibition already accomplishes that. Do the Viking helmet and ballet shoes really have anything to do with Sept. 11? There is something almost fetishistic at work. Does seeing them really amplify the horror or contribute to the memorial’s meaning? To the contrary: It distracts us. We become preoccupied with the private, not the public.

There are similar tendencies at the National 9/11 Pentagon Memorial in Washington. It contains what are called “memorial units”: cantilevered benches, each inscribed with a name of one of the 184 dead and arrayed along the attack’s flight path in a timeline of the victims’ ages — from 3 to 77. Their placement and positioning indicate whether individuals were killed on American Airlines Flight 77 or in the Pentagon itself.

Think about this, though: The heart of the nation’s military command is attacked, 184 are killed, and a memorial is designed based on victims’ birth years. It is as if the main point were the diversity of the murdered rather than the nature of the attack.

Some of the flaws in contemporary memorials may be related to their having become democratic signposts demanding attention for the dead in a crowded political marketplace where there is no clear notion of a public realm. But in the case of Sept. 11, this individualized approach may also be a form of avoidance, a reluctance to focus on the public significance of the attacks, their consequences, and the debates that continue.

The museum does, of course, recognize that these were attacks. And the exhibition’s second section is devoted to a survey of Al Qaeda. But it amounts to less than a tenth of the overall narrative; it is too narrowly conceived to convey the jihadist threat and its continuing evolution, let alone the responses and controversies it has inspired. Is it too soon for a more detailed history? It would seem so, but astonishingly, if the section about Al Qaeda were excised, little else at the museum would be affected; that is how disjointed the portrayal is. Without the Qaeda section, the narrative could almost be an account of a natural catastrophe.

We see this, too, in the exhibition’s closing gallery: a tribute to the idea of treating each Sept. 11 anniversary as a National Day of Service and Remembrance. We see images here of a church being rebuilt in Indiana, of rebuilding after the 2011 earthquake in Haiti, and of educational work in Afghanistan. In one respect, this turns the commemorations into homages to the sacrifices of relief workers and first responders. But it also involves avoidance. On the 10th anniversary of Sept. 11, when the White House offered guidelines for commemoration, it said that such efforts would show that we can withstand “whatever dangers may come — be they terrorist attacks or natural disasters.”

If attacks and disasters resemble each other, though, it is merely in individual experiences of trauma — this museum’s chosen domain — certainly not in the public consequences or historical implications of these events. Unfortunately, distinctions like these are now too eagerly ignored, perhaps because they bring up such unpleasant future possibilities.

But should they be ignored? Should this be the memorialization of Sept. 11 we are left with?