The point Rabbi Cohen makes is a good one: "He may have helped in secrecy many of the victims and many of the refugees but the question is 'could he have raised his voice and would it have helped or not?'" I know the "Pave the Way" foundation has honored Pius XII for what he did, but I've always wondered what difference it would have made had Pius XI been Pope during WWII and not Pius XII. Pius XI was known for his brusqueness and impatience with diplomatic niceties. He was the one who issued Mit brennender Sorge, which he caused to be read from every pulpit in Germany. He also said: "Spiritually, we are Semites," which made the link between Catholics and Jews obvious.
I guess people can argue forever about whether Pius XII did "enough," but the question of secrecy is pertinent and appropriate. If he had put Germany under an interdict or excommunicated anyone who cooperated with the Naziis, things might have turned out differently. Or not. But at least it would have been public.