The decades immediately after World War Two saw: (a) the spreading of ideas, rightly or wrongly attributed to John Maynard Keynes, that called for a larger government role in the economy; (b) the growing popularity of socialism; and (c) the creation of the United Nations, an event that gave a global voice to the citizens of lowincome countries and that provided statistics that, for the first time pointed to the big differences in living standards that existed between the so-called “developed” or “advanced” countries and the “underdeveloped”, or “developing” countries, and between the rich and the poor within specific countries. Those decades witnessed a period of fast growth in the activities of governments and especially in those of the central governments. The central governments of many countries assumed increasingly important and wider roles and functions. See Tanzi (2011) forthcoming, and Tanzi (2008). The governments of many countries tried to raise their tax revenue to be able to increase public investment, to create needed infrastructure and to provide better social services, such as education, health, and social assistance, to their citizens. In those decades the importance and the revenue needs of national or central governments grew and the literature on “taxable capacity” became a popular branch of economics. Especially developing countries needed more government revenues and more taxes to be able to grow.