On the limits of free trade in a Cournot world: When are restrictions on trade beneficial?

Abstract

This paper examines marginal deviations from free trade in an asymmetric Cournot world. We provide necessary and sufficient conditions under which: (i) small import tariffs, (ii) export subsidies, (iii) production subsidies and (iv) consumption taxes increase country-level as well as world social welfare and consumer surplus. We find that free trade is generally not optimal: some countries' tariffs or subsidies can always improve world welfare. Every country's export subsidy raises the average of world social welfare and consumer surplus. Finally, we rank the different policies and show that production subsidies are most likely to raise world social welfare, followed by export subsidies and then import tariffs, whereas consumption taxes never do.