The opening of a new museum by Yad Vashem is an event to be honored by the entire Jewish world. For Jerusalem to maintain its primacy, its centrality, the innovative creation of the 1950s had to be updated. If a museum does not evolve to meet the task of its time, it withers. Witness the cruel fate that has overtaken the Museum of the Diaspora.

Tom Segev has written of the competition between the United States Holocaust Memorial Museum and Yad Vashem, and Avner Shalev, its distinguished director, has denied it. Both miss some important points. Competition is good; institutions learn from each other, they challenge each other.

When we contemplated creating the U.S. Holocaust Memorial Museum, we looked to Yad Vashem as the model of an integrated institution; a museum that tells the story of the Holocaust, a research institution and archive, and an educational institution that teaches teachers and students the history of the Holocaust, its meaning and application to the new generation. And we certainly tried to do better.

And over the dozen years since Washington opened, the competition and cooperation with Yad Vashem has improved and empowered both institutions. Yad Vashem would not have been able to garner the support it has to create so magnificent a building and a campus without the looming presence of Washington.

The place from which you remember an event shapes the nature of that memory. Every historical museum is a dialogue between the historical event and the audiences that walk through its portals. So the story of the Shoah is told differently in Jerusalem than the Holocaust is told in Washington or New York, or the Final Solution is described in Berlin. Event, perspective and audiences all subtly influence the story that is told.

In earlier generations those who entered Yad Vashem knew the story; they had lived the events described. Thus, they could visit the memorial without seeing the exhibition. The exhibition merely had to allude to the events. Perpetrator artifacts would have been inappropriate to introduce to the generation that experienced this firsthand or whose parents were victims. But a new generation has arisen - conceived in freedom, unacquainted with exile - and to them the events must be portrayed, directly and graphically, far more graphically than was appropriate then.

When Yad Vashem first opened, Israelis could be confident that they knew the story, but after the misuse of symbols of the Holocaust - not only by Europeans and Arabs falsely and cruelly proclaiming that Israel is the new Nazism, but by Israelis accusing their own government of being Nazi-like and wearing Jewish stars to protest the Gaza withdrawal - our confidence should be shaken.

How is one to view a museum, to judge its success? The modern historical museum tells a story with a beginning, middle and an end, with emphasis and intensity; the narrative carries visitors through the museum. Like a symphony a museum must be organic; themes must be presented and developed. The institution is experienced whole by its visitors even if - as is clearly the case with Yad Vashem - it evolved over decades. How successfully will the creators be able to weave all the elements of Yad Vashem, its sculptural gardens, the Avenue of the Righteous, the Children's Memorial, the Art Museum, the Valley of Communities and Hall of Remembrance into one complete experience? I do not envy them the considerable challenge.

When I saw the new site during its creation I was concerned about the nature of the interrelationship between three primary actors in the Holocaust: the perpetrators, the victims and the bystanders.

In Washington, we devoted considerable attention to the bystanders, which is after all the American story. The sites of destruction in Poland and Germany show the nature of the crime and the mechanisms of destruction. They don't quite grapple with the perpetrator.

Yad Vashem is rightfully determined to present the Jewish perspective, as was New York's Museum of Jewish Heritage Holocaust memorial, but it must also present - and I use these words with great precision - the human story of the killers. This is essential. So convinced are we Jews that the killers were inhumane that we fail to confront the ultimate scandal: They were human.

Will a visitor to the new Yad Vashem understand the role of ideology and conformity, the desire not to lose face before one's comrades, and the killers' struggles to silence whatever conscience remained? Will they see the killers as part of our world - and thus a threat it - or apart from the world and thus bearing no relevance to it?

The crime against the Jews must be central, but the new museum must portray these crimes in context. Concentration camps were first developed to incarcerate German opponents of the regime; only much later did Jews constitute a majority there. Gassing was first used to kill German non-Jews who were an embarrassment to the myth of the master race. It was there that the role of bureaucratic killer was first nurtured, that the leadership of Belzec, Sobibor and Treblinka received their first training. Jehovah's Witnesses were martyrs. They could have been released from the camps had they renounced their faith. They died rather than convert; Jews had no such choice. Will Jewish memory be large enough to be both Judeocentric and inclusive?

Will the new museum with all of its power reach the multiple audiences that visit - Jews and non-Jews, Israelis and non-Israelis, Europeans and Americans, Israeli soldiers who must understand the raison d'etre of the state and of Jewish power, and who stand accused, falsely and viciously, by some in the West and in the Arab and Muslim world, of being the new Nazis? Will they understand - as American West Point Cadets and Naval Midshipmen are taught in Washington - the importance of military ethics, of recognizing the humanity of the enemy even while undertaking action against them? Great museums address multiple audiences of diverse sensibilities and contain enough to reach different visitors and touch their souls in diverse ways.

A generation ago it may have been sufficient to learn from the Shoah that the whole world is against us, that powerlessness invites victimization and thus the Jewish people must rely upon themselves and only themselves and assume adequate power to preserve themselves in the contemporary world. Those lessons are still valid, but not sufficient.

The challenges are many, the difficulties are great, the pitfalls obvious. It takes the endurance of a marathon runner to plan for years and bring it all together for a moment. It takes courage to open a museum - courage, wisdom and vision. I wish my colleagues well. I look forward to seeing their creation.