As to the German part, I have never believed that the vast majority had no idea what was going on. They chose not to know, or that is their story after they lost.

No, they had no way of knowing the full extent of the attrocities. If they saw Jews being rounded up, for all they knew, they were just being relocated. Also, the acts that were committed by the Nazis didn't all start and stop on a dime. They built up slowly, over time, which made eased them ing public acceptance. In his book, Thought They Were Free: The Germans, 1933-45 Milton Mayer wrote this:

 

“But the one great shocking occasion, when tens of hundreds or thousands will join with you, never comes. That’s the difficulty. If the last and worst act of the whole regime had come immediately after the first and smallest, thousands, yes, millions would have been sufficiently shocked – if, let us say, the gassing of the Jews in ’43 had come immediately after the ‘German Firm’ stickers on the windows of non-Jewish shops in ’33.

 

“But of course, this isn’t the way it happens. In between come all the hundreds of little steps, some of them imperceptible, each of them preparing you not to be shocked by the next. Step C is not so much worse than Step B, and, if you did not make a stand at Step B, why should you at Step C? And so on to Step D.”

Please explain the difference to me? I'm curious.

 

Your analogy of a Christian group building a church and praying to/praising Timothy McVeigh. Just who do you think that these Muslims in question will be praying to?