Well, I'm still not exactly sure what you're asking, but if I were to guess, it would be virtually synonymous with Clare's [paraphrase in post #443] of your question ---- "Do you think you could be born again and do what Hitler did?" ... So, I'll run with that.
In my opinion, I don't believe any born again believer would ever commit the atrocities that Hitler did. I would even take it further and say I don't believe the vast majority of unregenerated people would actually do what Hitler did if given the opportunity [and were not in a state of severe mental decline/disorder].
However, I suppose it's plausible for a born again believer to commit those crimes against humanity if they were suffering from some type of severe cognitive dysfunction. Therefore, only in the case of extreme exceptions like this would a born again believer ever opt to order the deaths of innocent people like Hitler did.
At it's core, the question at hand appears to essentially turn back upon the extent and efficacy of the change of nature that was necessarily accomplished in each person that become a new creature in Christ the moment they were indwelt by the Holy Spirit. [2 Corinthians 5:17, "Therefore if any man be in Christ, he is a new creature: old things are passed away; behold, all things are become new ...
Ezekiel 36:26-27, "I will give you a new heart and put a new spirit in you; I will remove from you your heart of stone and give you a heart of flesh. And I will put my Spirit in you and move you to follow my decrees and be careful to keep my laws."