"Worldwide"...riiiiight...

Demographically speaking, Japan is (obviously ) quite homogeneous; it's what makes it interesting - a mostly closed society that's really more of a tribe than a country. This doesn't prevent the Japanese media from trying to present it as otherwise, however.

Just sprinkle some foreign faces into whatever you're presenting to give it that "international " flavour. Much more effective if those faces are white (or can speak fluent Japanese) because in Japanese eyes, white equates to "high quality ". Want to teach English but not a native English speaker? No problem - your blue eyes and blonde hair will suffice. Japanese students won't know the difference anyway..