If you look at Japenese society it is an ancient society on the same level as European culture. Not only that but it is racially homogonous being fully Japenese on the islands. One can then see that the Jews, who racially bastardize a superior race, would feel threatened by the Japenese people, especially with the military nature of their religion Shintoism, along with the Bushido or sumarai code which promotes the highest honor for dying for Japan. One can see preceeding World War II that the American Imperium, run by the Jews, felt threatened by having an Asian Empire be a bulwark against American imperialism in Asia. Also against British interests, the Jews in Britain cut off the Anglo-Japenese alliance which would have benefitted Britain in the long run.
Along with this during World War II the propaganda was used to show the Japenese as barbaric people who comitted suicide against American soldiers and raped women since they were barbaric. After World War II after the American Imperium took over Japan, there was another conspiracy by the Jews in America to bastardize the Japenese people. Not only had Japan had her once mighty empire taken from her by inferior Americans but also the Jewish doctrine of democratism was promoted in Japan along with feminism to make Japenese women prefer careers over children, leading to a decline in the birthrate of the Japenese people. Along with this an infantile culture took hold in Japan over the once mighty culture of the sumarai and the Anglophilic capitalist nature of Japan took place to convert Japan into a full industrial economy.
One can also mention after World War II American soldiers and Negro soldiers were brought into Japan on "leave" to intermingle with and hopefully have children with Japenese women, leading to a decline of Japenese blood by inferior races, another conspiracy of the Jews.