admiring Hitler
This may appear to be a stretch for some but it occurs to me that Arnold's command of English is not perfect and in 1975 it was no doubt worse.
His use of the verb admire could have meant that he was impressed by Hitler. I assume that anyone would agree that one can be impressed, even awed and still despise an individual. I have seen many foreigners confused by our verbal nuances.
Someone more familiar with the German language would be better qualified to say whether this might be a possibility.