I've heard semiinary professor and pastor R.C. Sproul mention a book he found during
his academic studies in The Netherlands after WWII.
IIRC, the book contained a lot of Hitler's most personal/diary writings
and was titled something like "Hitler: Scourge of Europe".
Sproul says that Hitler even says (in so many words) that he had
"made a deal with the Devil" in his striving for supreme power.
I've looked for the book but not been able to find a copy/translation of it yet.
I have read extensively about Hitler and his henchmen (bios) and it is hard to argue with the idea that it was Hitler's intent to make such a deal.
If a person is spiritually inclined, they might ask how it is that an interesting young man with little apparent skill but towering ambition becomes an empire-building monster.
Hitler begs the question...where did his genius come from...it appeared later in life? Also, he knows things that, by his experience, education or reading, he should not know.