Is it ok with you if historians use the term "Jew" for Jewish person? I've never understood the disconnect on that one. Jap is derogatory, Jew is fine, and long as you don't say it as Joooo.
Do Jewish folks really think the word "Jew" is a slur? We've used it for so long and with no ill intent at church and Bible study..
However, it doesn't take a rocket scientist to figure out "Jap" is definitely a slur.