I have a perspective on Japan's attitude that you, an overseas Briton does not.
Your above remark is insensitive (probably unintentionally) but your apology to Prof. G. comes across as sincere.
I'm an overseas Briton. My grandfather was served in East Asia and witnessed atrocities he refused to go into detail about. He spent the rest of his life hating Japan, until the day he met my Japanese wife, his great grandson, and my wife's grandmother.