Blaming accounting rules for the current financial crisis is a little like blaming a flood on how you measure the depth of the floodwater. Entire asset classes have been submerged and whole banks have been swept away. That does not mean that changing the way we measure the depth will magic the deluge away.

But that is exactly what a growing number of politicians and bankers are proposing we do with fair value or mark-to-market accounting rules, which they blame for accelerating and magnifying this crisis.