Welfare-optimal trade and competition policies in small open oligopolistic economies

Standard trade theory claims that free trade is welfare-enhancing. We show that this is not the case if at least one sector of the economy is a Cournot oligopoly. In a simple small open economy with one oligopolistic and one competitive sector, welfare is an inverted U-shaped function of tariffs. Hence, an optimal tariff rate can be determined. The optimal rate depends on the number of firms in the oligopolistic sector. Below the optimal level, the competitive sector overproduces, i.e. oligopolistic good have a higher marginal effect on welfare. Increasing tariff rates stimulate the production of the oligopolistic sector by dampening imports. Under balanced trade, this reduces exports and production in the competitive sector, thus shifting resources to oligopolistic goods production. We also find that given certain levels of protection, perfect competition is not welfare maximal and, hence, not desirable. The finding explains why developing economies with imperfect competition are often reluctant to embrace trade liberalization and why, conversely, countries with high levels of external protection may be unenthusiastic about competition theory.