Immigration is here to stay thanks to the left making it a thing in every cultural zeitgeist so going back to before it was is a pipe dream. Best thing is limit and define those limits as much as possible, make it merit based (Brain drain potential enemies to weaken them) and accept actual persecuted refugees like Beors from SA and Hong Kongers who face life in prison or execution from the CCP for not wanting to live in a commie shithole.

Uyoku dantai is mostly Koreans who have Japanese names and hate the native Japanese.