Israeli Prime Minister Benjamin Netanyahu complained bitterly about international reaction to what he called Iran's drive toward nuclear bombs and its intention to destroy Israel, but he did not hint at a possible Israeli response.
"We encounter in the best case a limp reaction, and even that is fading," Netanyahu said Sunday. "We do not hear the necessary rejection, no harsh denunciation, no outcry."
Netanyahu spoke at Yad Vashem in Jerusalem, Israel's official Holocaust memorial authority, before hundreds of Holocaust survivors and their families, Israeli leaders, diplomats and others. A military honor guard stood at one side of the podium and a girls' choir on the other.
"If we have learned anything from the Holocaust," Netanyahu said, "it is that we must not be silent or be deterred in the face of evil."
In his address at the ceremony, President Shimon Peres recalled visiting the village in Poland where he was born. "Of all the Jewish homes and synagogues, not a single beam remains," he said.
Turning to the present, the Nobel Peace Prize laureate urged the world to confront threats of genocide, singling out Iran's nuclear program. Israel dismisses Iranian claims that it is not making nuclear bombs.
Peres said, "Weapons of mass destruction in the hands of those capable of mass destruction, with voices encouraging that destruction -- that is the most perilous combination to world peace."
The day is one of the most solemn on Israel's calendar. Restaurants, cafes and places of entertainment closed down across Israel Sunday evening at the start of the annual remembrance day. Local TV channels scrapped their light entertainment and substituted documentaries about the Holocaust and other similarly serious programming. Radio networks aired interviews with survivors and panel discussions about the significance of the genocide and lessons for the future.
At midmorning Monday, air raid sirens are set to wail across the country, marking two minutes of silence in memory of the victims.
Yad Vashem picked "Voices of the Survivors" as the theme for this year's commemoration. About 220,000 survivors live in Israel, all of them aging, some of them destitute and alone. In a statement on its Web site, Yad Vashem said, "The voice of the survivors is the link that binds the painful and tormented history of the Jewish people during the Holocaust to the future, to hope and to rebirth."
On Monday, Holocaust memorial day ceremonies include gatherings around the country, starting in the Israeli parliament, or Knesset, where people read the names of victims of the Holocaust. The project, called "Every Person Has a Name," is meant to break down the number of 6 million into stories of individuals, families and communities wiped out during the war.
A study released hours before the opening ceremony found that anti-Semitic incidents doubled worldwide last year compared with 2008. The Tel Aviv University report concluded that Muslim groups and radical leftists used Israel's bruising 22-day invasion to stop rocket attacks from Gaza, starting in late December 2008, as a wedge to expand their anti-Jewish agenda.
Researchers counted 1,129 incidents, more than double the toll of the year before and the highest in two decades of studies. Researchers said they found an "orchestrated and concerted attempt to delegitimize the Jewish people and Jewish state in Europe."
The report by the Steven Roth Institute for the Study of Contemporary Anti-Semitism and Racism charged that radical leftists and Muslim groups channeled Israel's invasion of Gaza into a campaign of anti-Semitism.
Dina Porat, the report's editor, said the study tracked only instances of physical violence against Jewish targets. "Verbal violence is violence, of course, but we don't count it," Porat said.