Huh, anyone besides me notice that Wano is in basically the OPPOSITE position that actual Japan was in?
In Japan, there was indeed a rebel uprising against the Shogun regarding Kaikoku (opening the country), but the sides were the opposite.
While the Shogunate was not thrilled, it lead Japan in taking the decision to open the country-- believing Japan would be otherwise invaded and conquered by foreign force, as China and India had basically been.
Many rebellious territories and factions espoused "Sonno Joi" (Revere the emperor, throw out the barbarians), and riled against the Shogun's decision to open the country.
I'm sure it's not a switcheroo just for the sake of it, but Oda's choice here is interesting.