A question for you
Are you interested in finding the truth about history and the role of the Pope in World War II, or are you merely interested in denigrating the Catholic Church? I am interested in finding the truth, and in a search for the truth, whether in religion or history, I find it useful to look at both sides of the story. In referring to the original topic of this thread, I suggested that you read a book by a rabbi - who is not a Catholic - called "The Myth of Hitler's Pope." He says that this is not true, and that the Pope did all he could to help the Jews. You can believe what he says or not.
I do know that the the author of "Hitler's Pope" is biased against Catholics, so I would take what he writes with a grain of salt. I also know that the sites that you reference are all anti-Catholic, so I would take that into consideration in my search for the truth. You are only presenting one side of the story. I think that you should look at what the other side is saying.
I read the letter that was supposedly written by Harry Truman. I'm sorry, but that letter is fake. Here are links from the "American Presidency Project" to actual letters that Truman wrote to Pius XII and the Pope's response.
http://www.presidency.ucsb.edu/ws/index.php?pid=12746&st=Pius+XI&st1=
http://www.presidency.ucsb.edu/ws/index.php?pid=13372&st=Pius+XI&st1=
The Concordant with Germany in 1933 was merely an agreement to disband the Catholic Center Party in exchange for a guarantee for Catholic religious freedom - and that agreement was immediately violated by Hitler, the chancellor of Germany. In 1933, Hitler was the legitimately elected head of state. No one knew the monster that he would become. It was not an endorsement of the Nazis - the RCC knew that the Nazis were opposed to Catholic religion, social teaching, and philosophy. It was merely an attempt to protect the religious freedom of the RCC in Germany and - as history shows us - failed - as the Nazis proceeded to persecute both the Catholics (by closing their religious houses and imprisoning their members) and the Jews.
In 1937 on Palm Sunday, the Pope issued a document called "With Burning Anxiety" that was read in every Catholic Church in Germany. In it, the pope listed the Nazi's violations of the concordant, affirmed Christianity's roots in Judaism, reminded the people that we are all children of God, whatever race or nation, and condemned the neo-paganism of the Nazis and their "mad prophet" - Hitler. The Pope concluded that against this (the Nazis) "There is but one alternative left, that of heroism."
In response, Hitler declared, "The Third Reich does not desire a modus vivendi with the Catholic Church, but rather its destruction with lies and dishonor, in order to make room for a German Church in which the German race will be glorified."
I don't believe Hitler was a Christian. Do you? Even if he had been raised in the RCC, he certainly didn't practice any Christian religion as an adult. If I was raised as a Muslim, yet didn't practice that religion as an adult, could I still be considered Muslim? Or if I was rasied in the religion of Islam, yet converted to Christianity as an adult, would I still be considered Muslim in your eyes? If I was raised as a Baptist, yet didn't practice that religion from the time of my teens, and commited horrible crimes, would you still consider me to be a Baptist?
It's very interesting that you would presume that I am not a Christian simply because I suggested that the whole story of Pius collaborating with the Nazis is anti-Catholic propaganda - like some of the websites that you provide to "prove" your point. Some of those websites are not even by Christian people. They even say that Hitler "practiced his own brand of Christianity" and was against the Catholic Church. So basically some of the sites refute your own point. You should do your own research. Try a library for starters. Read a book.