That's what happens when you live on the pacific rim, they could all choose to leave if they wished, not that it would ever occur.
However it does mean that Japan has a constant reason to update their infrastructure, which speaks volumes about how useless ours is, I also wonder if changes the overall attitude of people to either being far more vicious in their pursuits or more helpful and kind.
Either way, the threat of another nuclear catastrophe wont occur this time (just in case anyone is wondering).