Italy’s president on Friday denounced rising antisemitism and delivered a powerful speech in support of the Jewish people as he commemorated a Holocaust Remembrance Day overshadowed by Israel’s military campaign in Gaza and a rise in anti-Israel acts here. In a ceremony at the Quirinale Palace attended by the premier and leaders of Italy’s Jewish community, President Sergio Mattarella called the Holocaust “the most abominable of crimes” and recalled the complicity of Italians under Fascism in the deportation of Jews. Also Friday, Rome’s police chief ordered pro-Palestinian activists to postpone a rally in the capital that had been scheduled for...