Ohh! Nice relics Diglebat!
Well the "yellow menace" it's a usual subject on pulp novels, but I would say it's precisely Fu Manchu a twist on the subject, more than a racist topic I see him more like an agent of revenge for the abuses of the colonialist countries in asia.
A bit in the spirit of Capt Nemo.
But this is only a personal opinion, of course.