It's been used by native Americans too...long before Hitler.
Honestly I don't think the average American cares..unless maybe they are Jewish.
Correct. I'm sure it was the Jewish sensibility that was "injured" when seeing this. Given how very effective Jews are in political and legal dialectics, many of whom even are fluent in Japanese , perhaps complained to Japanese tourism ministry.
It's always interesting to see such a minority , the Jew, can be so influential and vocal.