For economists, the industrial countries had become a closed club excluding other countries after World War II, mainly because of their advanced innovations, capabilities to create increasing returns to scale and even to control the rules of the international system. This assumption was emphasized by the recurring difficulties and the inability of Latin American countries to develop a strong industrial base and to promote a steady growth. Consequently, the trade among countries had evolved according to a dual scheme establishing complementarity and confrontation between the center and the periphery: developed countries exchanged industrial goods with the others in return for their supply of natural resources.