Answer: The purpose of the footnote to paragraph 4 is that It provides an additional fact related to the Civil War.
Military leader with the real power in Japanese government (instead of the Emperor). This system was established by Minamoto Yoritomo as part of the Bakufu. Military style government set up by Yoritomo Minamoto in which the Shogun, a military leader, is in charge of the government.
It be the first passage that people mentioned it to children by saying"children pitching pennies" and stuff that"kicks and cuffs are their daily diet". Also, pollution is touched in this passage as it mentions "summer stenches" which are bad for poeple