Market turmoil is yet another lesson in need for international policy cooperation

World hasn't changed much since financial crisis, which showed an economic model based on widening inequality and uncontrolled capital flows is unviable

And so it begins. Shares are falling, currency markets are in turmoil. The price of oil is going through the floor, burning the fingers of speculators who have made the wrong bets on borrowed money. Welcome to the crash of August 2015.

Financial markets being what they are, there is every chance there will be a bounce on Monday. Investors will be sniffing out bargains and be hoping that the scale of last week's falls will prompt a response from central banks. Even in the most severe bear markets, prices never go down in a straight line. But don't be fooled. This could get ugly.

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