Economic autarchy (“autarchy” is just philosopher-speak for “self-sufficiency”) has a long pedigree in Thomistic (the most prominent strain of Catholic) philosophy. It goes back, indeed, at the very least to the man St. Thomas called simply “the Philosopher,” Aristotle, and continued unabated through St. Thomas himself, who elaborated on it in some detail. While it goes very strongly against globalization, of which most moderns from Austrian-school economists to Keynesians are unreconstructed fanboys, there is great reasoning behind it, which ought to be carefully considered by anyone thinking about the foundations of society.
Aristotle based his argument in favor of economic autarchy (and, indeed, autarchy in general) upon the nature of the state itself. Human society is made up not merely of the state, but of many levels of human community. (This discussion is from Book I, Chapter 2 of the Politics.) There is, of course, first and foremost the marriage, the unit of society which is ordered primarily toward procreation. (Unfortunately, Aristotle’s errors justifying slavery confuse this issue somewhat, but once those errors have been purged, that’s the bottom line.) From marriage arises the family, the community which is ordered to supplying day-to-day wants. Then comes the “village,” which St. Thomas called the vicus, made up of several families for the purpose of providing for those material needs which the family cannot fulfill. Finally, when villages unite into a complete community, we have the state, which exists for the purpose of the good life (which is, remember, the end of the men who are its members).
This state is a complete community, which contains everything that is necessary for the flourishing of its members. However, its members cannot flourish without fulfilling their material needs. Thus, the means for providing for the material necessities of its members must exist within the state. This is economic autarchy: the state must be self-sufficient in this way. Insofar as the state lacks what is necessary for human flourishing, it is defective. So goes Aristotle’s argument.
St. Thomas Aquinas naturally expands upon and perfects Aristotle’s argument, while accepting that argument on its own terms, as well. In the De Regno, St. Thomas goes on for some time about the self-sufficiency that is appropriate for the state (which he calls the kingdom) in the context of the production of food. St. Thomas begins by observing that a city (which is the political unit of the state, a topic which is more complex than this simple article will tolerate) may acquire its necessary food by one of two means: either by producing it itself, or by importing it. St. Thomas states unequivocally that it is much better to produce it than to import it.
Adopting Aristotle’s argument without even fully explicating it, St. Thomas agrees that the city which is more self-sufficient is better than the one which is less self-sufficient. Thus, since it’s important to be as good as possible, the city should endeavor to produce as much of its own food as it can, if possible all of it (at least the necessary foodstuffs).
However, St. Thomas adds further to Aristotle’s arguments. He notes that self-sufficiency is safer, because import routes are easily disrupted by war and by natural disaster, thus imperiling what the city needs to survive. He further notes that it’s bad for a city to have too many foreigners about (another argument taken from Aristotle), and that importing large quantities of goods increases the presence of foreigners. And he notes that tradesmen, not being engaged in physical activity, make poorer soldiers, should defense of the city be necessary, and that therefore having more tradesmen in the city would be a detriment. He further observes that having everyone packed closer together within the city proper, which is more likely when there is too much importation of goods, is more productive of civil unrest than having people more spread out, as will be the case when many of the people are engaged in food production.
His strongest argument, however, is that importation tends to produce vice in the city, and thus one should avoid it as much as possible. He states, “Since the foremost tendency of tradesmen is to make money, greed is awakened in the hearts of the citizens through the pursuit of trade.” One can find extensive justifications of this general thesis in other writings of St. Thomas, such as the Summa Theologica IIa-IIae Q. 77 Art. 4, with some illuminating discussing in Ia-IIae Q. 2, Art. 1. Aristotle also spoke on the same theme; for example, in the Politics Book I Chapters 7 and 8, concerning the unlimited nature of getting money with money. St. Thomas argues very forcefully that this is disastrous:
The result is that everything in the city will become venal; good faith will be destroyed and the way opened to all kinds of trickery; each one will work only for his own profit, despising the public good; the cultivation of virtue will fail since honour, virtue’s reward, will be bestowed upon the rich. Thus, in such a city, civic life will necessarily be corrupted.
All in all, these are forceful arguments in favor of economic autarchy.
We might add in our own day to St. Thomas’s justifications, that self-production allows full quality controls to be imposed. Recent difficulties with Chinese-made products in the United States come immediately to mind.
Now, St. Thomas did not argue that all trade was bad; indeed, such a proposition would be foolish. St. Thomas noted that “trade must not be entirely kept out of a city, since one cannot easily find any place so overflowing with the necessaries of life as not to need some commodities from other parts.” He concludes that “the perfect city will make a moderate use of merchants.” However, he provides very powerful arguments that the good state should seek the greatest possible degree of self-sufficiency.
These are good considerations for anyone forming his own opinions about political economy.

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