"Real historians differ on intangibles like degrees of influence, subtle contributing causes, implications, motive, and areas where contemporaneous evidence is poor."

so I guess my question should... " Who the heck is writing the history textbooks in Japan."... because the article is pointing out the current state of historical information available to the average Japanese citizen who did not go on to get their advanced degree in history.

You can not teach objective history or science if the textbooks are written by revisionists or others with a non-objective agenda. To paraphrase my computer science teacher - garbage in, garbage out.