Trade openness and government size


This Vox column by Paolo Epifani and  Gino Gancia on the relationship between trade openness and size of government is interesting because it both dismisses the received wisdom (of Dani Rodrik) and offers a new hypothesis:

More open countries have bigger governments…

Rodrik… argues that, in more open countries, firms and workers are more exposed to external risk and therefore demand more public insurance. Although plausible, this explanation fails to convince. In particular, if trade openness increases the demand for public insurance, this should show up in a surge of public transfers for social security and welfare. Our evidence shows however that, unlike government consumption, this kind of expenditure is uncorrelated with trade openness. Moreover, terms-of-trade volatility, which has been suggested as a measure of external risk, does not seem to (robustly) affect any kind of government expenditure…

We propose a different explanation. More open countries have larger public sectors because the cost of providing public goods is lower the higher a country’s involvement in foreign trade. The basic idea is that an expansion of the public sector crowds out private production, thereby reducing the domestic supply of exports. As long as the world demand for domestic products is downward sloping, a fall in domestic exports brings about a terms-of-trade improvement that partly compensate the increase in public expenditures. In other words, the rise in export prices shifts some of the costs of the public sector onto foreign consumers. This effect is stronger in more open economies, because the real-income effect of terms-of-trade movements is proportional to the volume of trade.