> + religion(these days, US outright ban any casual religious reference because it offend some believers, resulting modifying some manga/anime/game)
Religious sensitivities run high in the U.S., but criticizing or mocking (or advocating or practicing) a religion is a core territory of legally protected speech, and people very commonly criticize other people's religions and religious beliefs, including in mass media. There is no such ban.
> + national security
This is pretty complicated, but it appears that the courts will protect the publishers (not the leakers) of leaked classified information.
https://en.wikipedia.org/wiki/New_York_Times_Co._v._United_S...
> + ex-political party symbol(swastika, but they can't tell the difference between nazi symbol and Buddism symbol which is widely used in Japanese commercial products, especially manga/anime/game)
The U.S., differently from many European countries, does not prohibit the sale or display of swastikas, including when they are actually used to show sympathy for the Nazi Party.
> + child porno(their definition includes some commercial Japanese manga/anime/game which we believe not possibly be a child porn since it's a pure fiction and no real-life human being harmed).
There's still always a risk of obscenity prosecutions for comics in the U.S., and import restrictions on sexually explicit material are famously much more restrictive than domestic restrictions (which sounds like the very definition of a trade barrier). But there is a Supreme Court case specifically addressing attempts to ban sexual images that depict fictional children
https://en.wikipedia.org/wiki/Ashcroft_v._Free_Speech_Coalit...
The Court did not accept categorically banning these images.
