“It was not easy to be a child survivor after the War. I continued to hide. Why? My parents did not take me to the meetings with other survivors to not hurt the feelings of those that lost their children,” Ms. Lavi told the United Nations annual Holocaust Memorial Ceremony, held Wednesday at the world body’s Headquarters in New York.

“Even now 73 years after the War, I feel guilty that I survived,” she lamented.

Born in Poland, Ms. Lavi was two years old when the War broke out. One day when the Nazis appeared at the door of her home, her mother was desperate and gambled by putting her outside the window. It was winter and minus 20 Celsius, but Ms. Lavi held onto a pipe. It was freezing, but she survived.

Now in her 80s, Ms. Lavi said she has often wondered why the God saved her.

“Perhaps, he wanted me to do something big. I’m only an ordinary woman. No special achievements. But now I’m here, talking from the United Nations. This is the ‘big something’ that the God planned for me,” she said, noting that after her mother’s passing, she started publicly telling her stories for the sake of the future.

Another featured speaker was Thomas Buergenthal, a Holocaust survivor and a retired Judge of the International Court of Justice (ICJ), Professor at George Washington University Law School, in Washington, D.C.

He said he belongs to the ever-smaller group of still-living Holocaust survivors.

The world lost enormous intellectual, cultural, and scientific riches that would have benefited humanity as a whole, making the Holocaust a human tragedy of catastrophic proportions - Thomas Buergenthal, keynote speaker

“We have an ever-more urgent and sacred obligation to ensure that the memories of all victims of the Holocaust be permanently preserved, and to work for a world in which no human being will ever again has to suffer the horrors that this terrible genocide inflicted on them,” he emphasized.

Of the six million Jews who were murdered, more than a million were children, he noted.

“Think of the physicians, the scientists, the historians, the archeologists, the theologians, the poets, the philosophers, the writers, the engineers, the teachers and other professionals that these children might have become,” he continued, stressing that the world lost enormous intellectual, cultural, and scientific riches that would have benefited humanity as a whole, making the Holocaust “a human tragedy of catastrophic proportions” even without counting the other five million victims.

“No nation has a monopoly on goodness or on evil. Under certain circumstances genocide can take place in many of our own countries. That is why we must always be on the alert against this crime,” he said.

For his part, UN Secretary-General António Guterres, describing the Holocaust as a “culmination of hostility towards Jews across the millennia” and a “systematic campaign of extermination,” warned against signs that hatred, xenophobia and other types of discrimination exist in today’s world.

“Since hatred and contempt of human lives are rampant in our time, we must stand guard against xenophobia every day and everywhere. Across the world, the state of hate is high,” Mr. Guterres told the event.

Four days ago, 27 January marked the 73rd anniversary of the liberation of Auschwitz.

“The gargantuan horror of those 12 years, from 1933 to 1945, reverberates to this day,” Mr. Guterres said. “This annual Day of commemoration is about the past, but also the future; it is about Jews but also all others who find themselves scapegoated and vilified solely because of who they are.”

We must not lose sight of what went wrong - UN chief Guterres

The UN chief said that “genocide does not happen in a vacuum” and “the Holocaust was the culmination of hostility toward Jews across the millennia.”

“We must not lose sight of what went wrong,” he declared, warning against manifestation of resurgent hatred, such as the march of 60,000 people waving signs reading “White Europe” and “Clean Blood” in one capital two months ago.

The ceremony, hosted by Alison Smale, UN Under-Secretary-General for Global Communications, began with a minute of silence in honour of the victims and the survivors of the Holocaust.

General Assembly President Miroslav Lajčák said: “We are not here today just to remember the Holocaust. We are also here to remind ourselves of our collective failure to prevent it.”

He said that the Holocaust did not happen overnight. “We saw it coming, and we did not stop it.”

And, when it was over, a promise was made not to repeat it, “never again.” But, unfortunately, this promise has not always been kept.

“No, we have not had another world war. Nor have we seen anything on the scale of the Holocaust. But we have felt tremors in the ground. We have seen red warning flashes lighting,” he said, citing acts of genocide, systematic discrimination, anti-Semitism, racism, intolerance, Islamophobia and hate speech.

“Too often we did not have the courage to call things exactly what they are - and to act accordingly,” he said.

“So, we need to reflect on our inaction – and, indeed, our failures. But we must also use this occasion to inspire change.”

The Permanent Representatives of Israel, Germany and the United States, delivered remarks, and the ceremony include music by the UN Staff Recreation Council Singers and the UN Staff Recreation Council Chamber Music Society. Cantor Joseph Malovany of the Fifth Avenue Synagogue, also recited the memorial prayers.