Secondly, what of his twisted advisors? I think it would be fascinating to read tertiary literature of sentiment in that era and how people with those sentiments gained influence.
Secondly, the 'twisted advisors' shouldn't be seen as a few extremists, but rather the then-current alumni of a school-of-thought that was in the making for at least hundred years before WW2: Reactionary nationalism driven anti-semitism (as opposed to the anti-semitism that roamed europe before the 18th century).
Within these 100 years multiple people discussed 'solutions' and often the legitimate ultima-ratio seemed to be capital punishment, if the Jews weren't leaving by other means (As today some politicians would legitimize shooting illegal aliens at border-crossings).
All the anti-semites need to do to gain influence was to add fuel to the flames of the 'treason'-narrative.