Don Boudreaux at Cafe Hayek poses the following challenge to me:
But my problem with Rodrik's position runs even more deeply. If it's true that theory and evidence in favor of protectionism are sufficiently strong to warrant economists abandoning their conclusion that free-trade policy is generally sound, then why shouldn't economists -- led by Dani Rodrik -- also start exploring the potential benefits of intra-national protectionism? Surely a scholar not benighted with the free-trade "faith" ought to take seriously the possibility that, say, Tennesseeans could be made wealthier if their government in Nashville restricts their ability to trade with people in Kentucky, Texas, Rhode Island, and other states?
Indeed, such an objective scholar should be open also to the possibility that residents of Nashville can be made wealthier if their leaders restrict their ability to trade with people in Knoxville, Memphis, Chattanooga, and other locales in that state.
I suspect that if someone proposed to Dani Rodrik that he explore the wealth-creating potential of state-level protectionism, he would refuse. He would likely (and correctly) say that it's ridiculous on its face to suppose that such protectionism would make the people of Tennessee as a group wealthier over time. If my suspicion is correct, then to what would Rodrik himself attribute his out-of-hand dismissal of the notion that Tennessee tariffs might well make Tennesseeans richer? Would he realize to his chagrin that he is a benighted, faith-based non-scholar? Or would he instead understand that the case for an extensive, market-driven division of labor is so strong -- and that the political border that separates Tennessee from other states is so economically meaningless -- that it would be as pointless for a serious economist to explore the economic potential of Tennessee protectionism as it would be for a serious oncologist to try to cure a patient of cancer by bleeding that patient with leeches.
Let me confirm Boudreaux's suspicion that I would indeed be against imposing intra-state trade restrictions in general (or to be more precise, that I would have a strong presumption against them). So the question he asks is an important one. Why then do I not take an equally strong position against trade restrictions in international trade?
The answer is that the parallel is misleading in this context. The two situations are alike only in the limiting (and counterfactual) case where government-imposed tariffs are the only transaction costs blocking economic exchange across international borders. In reality, national borders demarcate political and legal jurisdictions, which means that there remain plenty of transaction costs which block economic convergence. Capital flows are hindered by sovereign risk and the absence of international regulation and lender-of-last resort functions, which create the kind of syndromes that I often discuss in this blog. Labor mobility is severely restricted. And differences in regulatory regimes impose severe transaction costs (estimated by Jim Anderson and Eric van Wincoop to be of the order of 40% in tariff equivalents) on international trade. In the presence of these transaction costs, free trade in goods (in the sense of zero import tariffs) is in general incapable of achieving rapid economic growth and economic convergence in poorer nations of the world. If you do not believe this, just ask the Mexicans.
Within this U.S., economic convergence is achieved because there is a common constitution, a federal judiciary, nation-wide financial regulation, and free flow of labor. This ensures that a lagging region (such as the South until recently) catches up by a combination of capital coming in and labor moving out. Neither of these channels are operative in a world economy that is divided into nation-states. Removing restrictions on international trade in goods, services, and capital simply does not do it. Trade ends up being too small, and capital flows in the wrong direction (from poor to rich countries).
There is of course the option of global federalism (creating a U.S. or an EU at the global level)--but that does not seem a realistic option anytime soon. I doubt that Don Boudreaux would go for it in any case. (See here for a more extensive discussion of these issues.)
Now, there is still the question of how trade restrictions may help in the kind of imperfectly integrated world economy I have discussed. I think the answer is that when you are stuck with a labor force that is producing at low levels of productivity, there exists a bunch of arguments having to do with learning and (domestic) market failures under which subsidization of tradable activities could speed up your economic growth. There also exists a bunch of historical and current instances where the evidence seems to have lined up with these theoretical presumptions. That is why I am not a free trade fundamentalist and believe that there are circumstances under which trade restrictions may serve a valuable function.
UPDATE: Brad DeLong does not express my views accurately. He writes:
... Dani Rodrik's country whose "labor force that is producing at low levels of productivity" is doing so because it has lousy political institutions: it lacks the "constitution... judiciary, nation-wide financial regulation, and free flow of labor" that have underpinned economic growth in the rich post-industrial core. The poor country is poor because its government is incompetent, and corrupt.
No, the argument that poor countries are and remain poor because their governments are incompetent and corrupt is one of the absurd reductionisms of the day which I do not believe in and have written against. The point I made was that a poor country would have the real prospect of converging in living standards with rich countries if international economic integration were near-total (involving free labor mobility, truly integrated capital markets, and a transnational set of regulatory, legal and political institutions that underpin this integration). In the absence of these, trade liberalization does not get you there. You are in a second-best world and you need to think appropriately. The idea that developing countries cannot employ industrial policy in such a world to good effect is downright silly.
Here is a thought experiment: does anyone really believe that China would have grown as fast as it did if it had removed all its tariffs and trade restrictions in 1978, instead of liberalizing strategically and sequentially--first in agriculture, than in industry, then on the export side, and only later in the 1990s on the import liberalization side? There are many reasons why the Chinese strategy worked, but one of them is that it protected employment while industrial capabilities were being built up.