Every evil has a reason, but all evil has no excuse. I can't be obliged to be evil just because evil comes from above; I can't be worthy to be evil just because everyone else is so evil: I can't even have the right to be evil to others just because someone is evil to me. 
every specific evil must be condemned. If respect for life must be in the single digits, so must the condemnation of sin.
A certain Nazi officer poisoned hundreds of Jews in a concentration camp. He was carrying out the orders of his superiors, and the orders were overwhelming...