Strategic trade policy in general oligopolistic equilibrium: The case of import tariffs

In a two-country model of general oligopolistic equilibrium with technologically heterogeneous sectors, I study how, in a home-market scenario, a unilateral rise in uniform cross-sector import tariffs affects wages, countrywide profits, and welfare. Firms face resource constraints and wages are simultaneously determined. Economy-wide protectionism reduces the foreign wage without affecting the domestic one. Domestic countrywide profits benefit from a small rise in uniform tariffs, whereas the foreign counterpart is damaged. Domestic welfare is unambiguously hindered. Hence, the general-equilibrium cross-sector perspective goes against the textbook version theory of the optimal tariff in partial equilibrium. Rationalization of these effects suggests a political-economy view on tariff formation in general equilibrium. Then I extend the model to segmented markets, considering uniform specific and ad valorem tariffs for bilateral and unilateral trade policies.