In January of 1991, economist Lawrence Summers took a leave from his Harvard professorship and moved to Washington to work for the World Bank. His job was to create economic plans for countries in need of aid. It was a weighty task, but Summers relished the challenge. Using the kind of provocative imagery for which he would become notorious, he once explained that countries without a strong central government and vigorous private sector were like "a cripple . . . with no legs, pushing himself around on a crude board with wheels, surviving only with begging and trying to look...