Deborah E. Lipstadt, Dorot professor of modern Jewish and Holocaust studies at Emory University, is the author of " History on Trial: My Day in Court with David Irving ." She was the target of a British libel lawsuit by Irving, a historian she said had become a spokesman for Holocaust denial. Lipstadt won the case in April 2000. The opinions expressed in this commentary are hers.

(CNN) When Elie Wiesel felt justice was in jeopardy, he spoke out. And people in the highest reaches of power listened. Two incidents make that exceptionally clear.

In 1978, when President Carter established a United States Commission on the Holocaust with the intention of creating a museum, his staff informed him that only Wiesel could chair it. He was the "one person" capable of this job. According to Carter's advisor , Stuart Eizenstat, Wiesel "ha[d] the stature and . . . had become the worldwide spokesman for Holocaust survivors and indeed for the victims."

But trouble soon ensued. Carter, for political and ideological reasons, wanted to make the museum a memorial to all victims of the Nazis' murderous ways. Carter's plans would even have included Eastern European groups who collaborated with the Nazis in killing Jews.

Wiesel believed that, while others should be memorialized there, the museum must primarily commemorate the attempt to wipe out all of European Jewry. It was this act of state-sponsored genocide, this desire to murder all Jews irrespective of where they lived, their age, or their ability to do the Germans any harm, which made the Holocaust unprecedented.

To subsume their deaths within all the evil the Germans did would be fail to learn the lessons of this tragedy. Wiesel adamantly refused to accept the White House's attempt to play with history for ideological purposes. And he won. Today the United States Holocaust Memorial Museum uses the Jewish tragedy to illustrate the danger of all forms of genocide. By relying on the specific, it teaches a universal lesson. This was Wiesel's message.

Bitburg and Bergen-Belsen

In 1985, Wiesel took on another president, this time even more publicly and directly. Known as the Bitburg Affair, it had its roots in clumsy efforts by President Ronald Reagan and German Chancellor Helmut Kohl to celebrate America and Germany's postwar friendship. In a private, quiet exchange at the White House, Kohl asked Reagan if, during his forthcoming trip to Germany, he would accompany him to a German military cemetery for a wreath-laying ceremony and a symbolic handshake.

Kohl had been deeply hurt when Germany had not been included in the 40th anniversary commemoration of the landing at Normandy. Organizers believed it inappropriate to have the perpetrator of the war present at the commemoration of the deaths of tens of thousands of Allied soldiers. Kohl, however, interpreted this not as a reflection of historical events but as a snub that indicated that, in the eyes of its Western allies, Germany was still a political and moral outlier. Anxious to overcome this perception, Kohl asked Reagan to join him in the visit to the cemetery.

Then, shortly before the visit was scheduled to take place, the media reported that a group of Waffen SS soldiers were buried at Bitburg. The president of the United States would be laying a wreath at a cemetery that contained the graves of those Germans most closely associated with the murder of the Jews, Gypsies, and so many others.

Wiesel was scheduled to receive the Congressional Gold Medal from Reagan a few days before the trip to Germany. With the world media present and the entire ceremony being broadcast live, Wiesel turned to Reagan and in a voice laced with pain implored him not to go. He told him: "That place, Mr. President, is not your place. Your place is with the victims of the SS. . . The issue here is not politics, but good and evil."

Reagan went to Bitburg anyway. He looked stiff and uncomfortable while there. But, subsequent to Wiesel's remarks, his supposedly inviolate schedule had been changed and a visit to the concentration camp Bergen-Belsen had been added. A visibly shaken Ronald Reagan emerged from the camp after an hour-long visit. He had spent precisely 10 minutes at Bitburg.

Again and Again and Again

While his personal tragedy, the one that took his parents and siblings, was the Holocaust, Elie Wiesel's gaze extended far beyond that. Though he thought the Holocaust "singularly" unique, he was shattered that in its wake the world seemed to have learned nothing from it. Cambodia, the former Yugoslavia, Rwanda, Darfur, and the Sudan all suggested that rather than "Never Again," it was far more accurate to say, "Again and Again and Again." Deeply troubled by these events, he spoke out about them again and again.

His book, "Night," has sold over 10 million copies and, with the exception of Anne Frank's "Diary," is probably the work most responsible of bringing the Holocaust to the attention of the world. Given its great impact, it is ironic that when he first sought an English language publisher for the book, which had already been published in France, it was repeatedly rejected. Many publishers believed there was no market for a book on this topic. They were not wrong. It sold fewer than 2000 copies in its first year after publication. The fact that today it is considered an iconic work — when I ask university students what they have already read on the Holocaust they invariably mention "Night" — is a tribute to Wiesel's ability to bring the Holocaust to the world's attention.

In 2005, President George W. Bush asked a small group of Americans to represent him at the 60th anniversary of the liberation of Auschwitz. Elie Wiesel was a member of that delegation, as was I. It was a freezing cold January day. As the sun set early in the afternoon, the winter wind blew across the open expanse of the camp.

Despite being bundled up in many layers of winter wear, I was shivering with cold. I was sitting next to Wiesel and, without thinking, I turned to him and said: "Oh, I'm so cold." As soon as the words emerged from my mouth, I realized that I had just complained about the cold to someone who had endured this chill with only a pajama-like uniform and ill-fitting shoes to keep him warm. He did not then have the parka and snow boots in which I was now encased.

Mortified at my insensitivity, I said to Wiesel: "I'm sorry. Certainly this cold is nothing like what you experienced as an inmate sixty years ago." Then I apologized again. "I'm so sorry." Wiesel leaned over towards me, touched my hand, and with a sad smile said: "Don't apologize, Deborah. I am cold too."

On his precious Sabbath, when the news of his death reached us, all who value justice, hate evil, and treasure truth felt a chill. The world was now just a bit colder.

Note: A previous version of this article stated that Elie Wiesel was awarded the Congressional Medal of Honor. He was awarded the Congressional Gold Medal and the article has been updated to that effect.