I think official japan already spend enormous amount of money keep the nikkei above 8.000. It seems essential for the banking sector and thus for large parts of the economy that portfolio holdings need not be devaluated.
Now with the nikkei dipping at 8.000 the thing could further destabilise IMO. Don't forget that the japanese debt to GDP ratio is at 150% or something like that, with huge increase in recent years. Before everything is really devastated I doubt real recovery can take place. They already tried everything in the world wide prospering nineties. Why should it work now without them solving their major problems or let the market solve them?
peace