Faith + Reason = Truth

Wired News has a story about MySpace invading Japan.  It details the current dominant player there, called Mixi, and ponders the cultural differences between the two social networking sites, as well as strategies that may or may not work.  The reason it won't work for MySpace Japan is the same reason why someone can't move into the U.S. and takeover:  MySpace already has network effects at work here that serve as the most effective barrier to new players.  Mixi has those same network effects already in place in Japan.  End of story.
The SMART play would have been to partner with Mixi, creating a solid foundation for a trans-Pacific social network.   That way, they're not re-inventing the cultural wheel that the dominant domestic player has already established and not wasting resources trying to break into something they won't be able to break into.  The partnership then approaches the dominant social networks in Korea and China, then spreads westward to India and Russia, then through Europe, building momentum all along the way.  You would not attack all fronts simultaneously, because if you have a strategic error, you'd want to work that out one partner at a time rather than dooming the whole concept to failure.