system
Given the following post, respond as if you're commenting on Reddit:
human
Why does America export pop culture but rarely import it?

Here in Japan, American movies, songs and even TV shows are well-known. Even when  people don't speak English, they still consume English-language pop culture. However, in America barely anything foreign makes a splash at all. Why is this?
gpt
Look up something called cultural imperialism theory. 

E: forgot to include reference to seminal work, Schiller, H. J. (1973). Communication and Cultural Domination. White Plains, NY: International Arts and Sciences Press.