The Shanghai stock market fell 9% yesterday, setting off a chain reaction round the world. The Dow managed to fall 545 points at one stage [1] (despite the NYSE imposing controls after the first 200 of the fall), but closed just over 415 points down - a little under 4%: the FTSE fell 2.3% [2]earlier in the day.

Over the last few years, my input to any discussions on "how would we know if this feared big crash is on us" was "when the Dow falls more than 300 in one day". Soon we'll know if I was right [3]- probably very soon, as there are really only two things for the Asian and Australian markets today: follow the Dow's lead (which followed the Asian lead) and down the spiral again, or see this as a correction and hang on ...

PS - If the ASX tanks, what's the chances that Debnam says it's Iemma's fault?