We're all Shanghai gamblers now.(INVESTMENT: STOCK MARKETS)(Shanghai stock market in the global economy)

You might think yourself a fairly cautious investor. Maybe you dabble in a few shares and unit trusts, probably in major, well-established markets such as the US, Japan or Germany, as well as London. Emerging markets, and in particular the wild frontier that is China, you might reckon best left to professionals. And if you do occasionally take a few exotic punts, you're very likely to restrict them to 10 per cent or so of your portfolio.

But if you believe your exposure to the great Eastern dragon is modest or negligible, you're wrong. It turns out that we're all playing the Shanghai market now. Where once global stock markets took their cues from the Dow Jones or the S&P500, the two big American indices, they are now …