I heard it suggested somewhere that Amon Goeth had a personality disorder. He was in a psych facility when arrested, prior to execution. As a layperson, it's hard for me to find more than that, let alone evaluate the Nazi Military on a large scale.
The horrible reality of the Nazis is that perfectly sane rational normal people murdered starved and tortured innocent men women and children. But there were also a larger than average number of psychopaths that found their way into organizations like the SS. (If you dreamt of torturing and killing people and you heard of an organization that was torturing and killing people you would probably join to)
After WW2 many German officers began pushing a myth that the Wehrmacht was clean. They tried to rewrite history (they actually succeeded in large part) to make it seem like only the SS committed crimes and the Wehrmacht was just a fighting force like any other.
The truth is that all levels of the German Military participated in war crimes and genocide. Certainly a SS unit would be more responsible for crimes but Wehrmacht units made up of average German soldiers also committed atrocities without SS involvement.
How correct is the notion of "clean Wehrmacht"?
I'm going to get on a soapbox for a moment. One lesson we learned from WW2 is that the Nazis weren't monsters. They were normal people who committed unforgivable crimes. You, me, the sweet old in the supermarket, everybody; in another place in another time we could do the same.
" The Milgram experiment on obedience to authority figures was a series of social psychology experiments conducted by Yale University psychologist Stanley Milgram. They measured the willingness of study participants to obey an authority figure who instructed them to perform acts conflicting with their personal conscience.
The experiments began in July 1961, three months after the start of the trial of German Nazi war criminal Adolf Eichmann in Jerusalem. Milgram devised his psychological study to answer the popular question at that particular time: "Could it be that Eichmann and his million accomplices in the Holocaust were just following orders? Could we call them all accomplices?"
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