Dynamic Gains from International Trade with Imperfect Competition and Market Power

This paper revisits the gains from trade under imperfect competition by explicitly modeling strategic competition and entry. The papers highlights a welfare cost of imperfect competition, due to inefficiently high entry. Through increasing competition, international trade lowers price–cost markups and reduces excessive entry. This adds on a "competitive" channel for gains from trade to the well-known "product diversity" channel from previous literature. Both channels will increase the return to investment and raise the steady-state capital stock. An alternative case is possible, however, where there is inefficiently low entry. In that case, trade tends to be "anticompetitive," raising price–cost markups and encouraging increased entry.