W hat is good for Ambac, the bond insurer, is good for the country. Well, per- haps in the short run if it prevents a run on the shadow banking system - our over-leveraged system of financial conduits that have provided the spending power to keep the US economy going in recent years. But not in the long run.

The Ambac business model is as faulty now as was chairman Charles Wilson's forecast for General Motors more than a half century ago. Wilson's response to a US Senate inquiry in 1955 implied that GM's near monopolistic control was beneficial to the country. It was, until the domestic motor industry fell asleep at the wheel of innovation and became more concerned with placating its labour unions with