Paul Krugman began his Tuesday column for the New York Times — inevitably, about the blackout — with one of the few truthful statements I can ever recall him uttering: "We still don't know what started the chain reaction on Thursday." But after that admission, he proceeded to spend the next 649 words of his column telling us exactly what caused the blackout. Can you guess? On Monday, Krugman explained it to the German magazine Der Spiegel: According to American economics professor Paul Krugman, public services have been cut back in many areas to the benefit of "tax breaks for...