I'd like to link to a previous thread. Not only because of usual reasons of relevancy, but also because user /u/Aleksx000 also tackles the question of whether Bismarck actually even said the quote:
There are also links to other previous forms of the question contained in the comments of the thread I linked above.
This is to take nothing away from any other surviving responses. I just thought the question of whether Bismarck actually said it was an interesting wrinkle to the usual question.