What are the motifs in A Thread of Grace by Mary Doria Russell?

Evil is certainly a recurring idea in the story. Hitler's childhood could not have been any more dysfunctional. A domineering, paranoid mother who passed on her neuroses to an only son who was effeminate and deeply ashamed of his heritage was a recipe for Hitler's over-inflated conclusion about his own superiority. Werner Schramm's fear of being sterilized and marked for his sister's deformity resulted in his blind acceptance of a prestigious position where his job was to murder human beings. When the Nazis abused their power, it was out of fear that they might not dominate the human race that was, in their opinion, seriously flawed with the exception of the Aryans. Once they had some successes, they began to fear the loss of the power they had attained. Renzo Leoni's act of bombing a hospital may have seemed evil to others, but Renzo knew what it was like to be caught up in the moment, confused and afraid. It is not that Russell wants us to feel sorry for Schramm, or Hitler or even Leoni, but simply that there is always a complex underpinning to peoples' behavior.