Even as a saxophone player in a 1940s swing band, Alan Greenspan had a passion for staying in control. While some of his fellow musicians smoked marijuana or snorted stronger drugs, the future chairman of the Federal Reserve Board kept track of the band's money. "Some people used to complain that the band was smoking these funny hand-rolled cigarettes," recalls Washington lawyer Leonard Garment, another sober-sided member of the touring ensemble. "But Alan was clean as Clark Kent: he handled the books and never ran a deficit."
Yet since the U.S. Federal Reserve raised short-term interest rates on Feb. 4 and...