The grainy, often badly focused black-and-white photographs from the Eastern front are of Jews and others being tormented, humiliated, shot and hanged, of corpses in mass graves--the workaday world of genocide. Such has been this century's dark side, these photographs might have scant power to shock but for the significance of their amateurishness: 80 percent of the photos in the exhibit were taken by ordinary soldiers in the German army, and most record actions by the regular army, not the SS, Waffen-SS or the Einsatzgruppen killing squads.

Consider the remarkable reaction to the presentation of history by the Hamburg Institute for Social Research in the photographic exhibit "The German Army and Genocide." That the army on the Eastern front was immediately, deeply and constantly involved in genocide and other war crimes is, says Dr. Bernd Greiner of the Institute, not news to historians. But many Germans have clung to the conviction that Nazi criminality was the work of a lunatic fringe and corrupted members of elites, such as doctors and lawyers. Did not the Nuremberg war crimes tribunal give the army a moral acquittal?

No. The tribunal said the army, filled by conscription, would not be categorized, as the SS was, as a criminal organization. But the tribunal also said the army abandoned the rules of warfare and was implicated in genocide.

The photo exhibit, seen so far by a million people in Germany and Austria, makes graphic the wide sweep of possible complicity in murder: Every family had at least a father, son, uncle, cousin or nephew in the army. And the conflagration of soul-searching begun by the exhibit has been fueled by two publishing events.

Shortly after the exhibit opened in 1995, Victor Klemperer's wartime diaries were published. Klemperer, a Jewish academic married to a non-Jew, managed by luck and stealth to survive the war, during which he wrote that by early 1942, drawing upon common gossip, he could describe the hierarchy of concentration camps, including killing camps in eastern Poland. (He cited Treblinka by name.) A 14-part television series has been made from the diaries. The publisher, who Greiner says expected to sell 5,000 copies of the diary, has sold a half-million.

Germany's unending self-examination was further agitated by the 1996 publication of Daniel Goldhagen's "Hitler's Willing Executioners: Ordinary Germans and the Holocaust." Goldhagen's thesis is that German society was saturated by an "eliminationist anti-Semitism" which produced a high degree of voluntary participation in genocide. Goldhagen's idea--that Hitler merely unleashed a cultural latency and fulfilled the sick logic of Germany's history--was extreme. However, it acquired extra resonance in the context of the exhibit of photographs taken, in a matter-of-fact manner, by ordinary men doing extraordinary evil.

The exhibit has been seen in 34 German and Austrian cities (after the 1938 Anschluss, many Austrians were drafted) and 50 more have requested it. It was scheduled to open this month at the Cooper Union in Manhattan, but that has been delayed indefinitely pending an expert panel's review of each of the approximately 1,000 photographs.

The review was occasioned by a Polish historian's demonstration that eight to 12 photographs taken in three Ukrainian villages are of victims of Stalin's NKVD. Even this did not help the German army's reputation: In one village the NKVD killed 600 suspected collaborators; then three weeks later the German army arrived, forced Jews to disinter the 600 and shortly thereafter participated in murdering 200 of the Jews.

The exhibit has catalyzed the cleaning out of some dark recesses of Germany's mental attic. Several dozen people have come to the exhibit bearing family albums containing photos like those in the exhibit--photos of soldiers cutting the beards off Jewish men, photos of bodies hanging from street lamps. Some of these photos are displayed in albums, like photos of family vacations. In Austria a visitor to the exhibit identified the soldiers in a gruesome photograph: He had been in their unit.

The exhibit has been cathartic, revealing something still boiling beneath the crust of Germany's normality. Greiner says, "We, the originators of the exhibit, were expropriated of our product. The public took over." Which is proof of Germany's healthy, fact-facing vigor, even 54 years on.

In America, where approximately 1,000 World War II veterans die each day, a different kind of catharsis is occurring. The cultural mechanisms of mass memory--movies (e.g., "Saving Private Ryan"), books (e.g., Tom Brokaw's "The Greatest Generation"), the drive to build a World War II memorial on the Mall here--attest that the attic of our national memory is an inspiring place to pass some time.