TANSTAAFL. Every action taken has costs, and sometimes those costs are borne by those who had no say in the matter (“negative externalities” to use the technical term). The existence of externalities is often used to justify government involvement in markets (pollution tends to be the common example). Lately, however,
protectionists scarcityists have begun using that argument to promote their policies, noting job loss as an externality. Some, more generally, claim “practical people not tied to free trade dogma understand that trade sometimes is good and that it’s bad other times.”
It certainly is possible that, any given transaction, may have enough unforeseen negative consequences as to have negative net benefits. However, the bar needed to justify government action is high:
From a purely economic perspective*, protectionists have two tasks before them:
1) Prove that imports cause greater net harm than domestic production
2) Prove the proposed solution minimizes the net loss (or, inversely, maximizes net benefits). This is where comparative institutional analysis comes in.
The mere existence of condition (1) is neither necessary nor sufficient to justify government intervention. If the cost of government intervention exceeds the benefits therefrom, then even though the free market option has a net loss, it is the optimal solution because the resulting intervention would make matters worse!
The existence of condition (1) may require collective action to solve, but it may be more cheaply solved via non-government collective decision making (ie, a firm).**
There may be cases where government decision making is the lowest cost option. However, it is very much a case-by-case basis. Blanket legislation (like a tariff) does not allow for the necessary flexibility to make such decisions. In order to minimize costs (and thus maximize net benefit), freedom must be given first preference, with the burden of proof upon protectionists.
*There could be many other arguments for protectionism, such as legal, or national defense. I shan’t get bogged down in a discussion here. I’ll leave that to the experts.
**For a more in-depth discussion on this point, read The Calculus of Consent by James Buchanan and Gordon Tullock, in particular Chapter 5.