Amen. I have also read Cornwell's "book". When you add to the fact that it is full of lies and distortions (and the very first one is the cover photo on the book, which was taken of then-Cardinal Pacelli in Germany, but well before Hitler came to power) the fact that Cornwell himself is a failed seminarian who has written a number of books viciously attacking the Church, then you see where the hatred is coming from.
I too have friends who swallow the anti-Catholic propaganda hook, line, and sinker. They at least have an excuse of sorts, because they are children of Holocaust survivors. I can see how looking around for people to blame would be their natural reaction, but in this case they're blaming a man who did all he could with the limited power of the Church ("How many divisions does the pope have?") to save as many as he could. In his position, he had to work quietly behind the scenes, because public pronouncements simply attracted the attention of the Nazis. When the Dutch bishops condemned the Nazis, they were brutally silenced, and the Nazis stepped up their extermination of Dutch Jews.