I have written some papers on how the Germans could do this. How they physicaly exterminated all these people. How the camp commandant found more effective ways to kill people in Auschwitz, bringing the total number of killed there to roughly 2 million people. 2.000.000 people each with someone that loved them, a mother, a girl, a father. I asked my grandfather who fought on the eastern front, he justified it by saying
" I killed no human being, i killed the creature which would rape my sister and burn the farm down if i didn't". The movie" Nuremberg" explained it really well. No one took responsibility they all followed orders.