“Greenspan devoted his professional life to understanding how the U.S. economy worked, first as a private-sector forecaster when America was emerging as the economic superpower following World War II. Later, as technology, global trade and financialization refashioned business, he achieved a level of fame and influence rivaled only by U.S. presidents. Greenspan, the second-longest-serving Fed chairman (just behind William McChesney Martin, 1951-1970), husbanded that power to build up the central bank’s political independence.”