There are reasons to protect local culture, of course. American culture is The Borg, assimilating all. Drop a VCR and a TV in a remote Amazonian village, return a year later, and what do you find? Nothing, because you forgot to supply the generator. But leave one of those, and within six months the kids will be running around saying “No Luke I am your father” and making whoom-whoom lightsaber sounds. This fact gladdens the heart of some, since it shows that American values – freedom, justice, explosions – are universal.
Cultures should never be viewed as a static thing. Borrowing ideas from others (even Americans) improves rather than diminishes a culture.