Zenit, the international news agency that covers the Vatican, learned that the origins of the document extend to a letter written in 1946 by Isaac Herzog, chief rabbi of Jerusalem, to Pius XII. In it, Herzog thanked the pope for helping Jews during the Holocaust and for sheltering ‘thousands of children who were hidden in Catholic institutions.’ He then requested that these children be returned to their original families. Which, as we now know, is what happened. “In short, what the critics of Pius XII are suffering from is a heady dose of Rathergate: they willingly took the bait and...