Tag: tariff

Tariff dumbnamics in the penguin island autarky

The formula behind the recent tariffs has spawned a lot of analysis, presumably because there’s plenty of foolishness to go around. Stand Up Maths has a good one:

I want to offer a slightly different take.

What the tariff formula is proposing is really a feedback control system. The goal of the control loop is to extinguish trade deficits (which the administration mischaracterized as “tariffs other countries charge us”). The key loop is the purple one, which establishes the tariff required to achieve balance:

The Tariff here is a stock, because it’s part of the state of the system – a posted price that changes in response to an adjustment process. That process isn’t instantaneous, though it seems that the implementation time is extremely short recently.

In this simple model, delta tariff required is the now-famous formula. There’s an old saw, that economics is the search for an objective function that makes revealed behavior optimal. There’s something similar here, which is discovering the demand function for imports m that makes the delta tariff required correct. There is one:

Imports m = Initial Imports*(1-Tariff*Pass Through*Price Elasticity)

With that, the loop works exactly as intended: the tariff rises to the level predicted by the initial delta, and the trade imbalance is extinguished:

So in this case, the model produces the desired behavior, given the assumptions. It just so happens that the assumptions are really dumb.

You could quibble with the functional form and choice of parameters (which the calculation note sources from papers that don’t say what they’re purported to say). But I think the primary problem is omitted structure.

First, in the original model, exports are invariant. That’s obviously not the case, because (a) the tariff increases domestic costs, and therefore export prices, and (b) it’s naive to expect that other countries won’t retaliate. The escalation with China is a good example of the latter.

Second, the prevailing mindset seems to be that trade imbalances can adjust quickly. That’s bonkers. The roots of imbalances are structural, and baked in to the capacity of industries to produce and transport particular mixes of goods (pink below). Turning over the capital stocks behind those capacities takes years. Changing the technology and human capital involved might take even longer. A whole industrial ecosystem can’t just spring up overnight.

Third, in theory exchange rates are already supposed to be equilibrating trade imbalances, but they’re not. I think this is because they’re tied up with monetary and physical capital flows that aren’t in the kind of simple Ricardian barter model the administration is assuming. Those are potentially big issues, for which there isn’t good agreement about the structure.

I think the problem definition, boundary and goal of the system also need to be questioned. If we succeed in balancing trade, other countries won’t be accumulating dollars and plowing them back into treasuries to finance our debt. What will the bond vigilantes do then? Perhaps we should be looking to get our own fiscal house in order first.

Lately I’ve been arguing for a degree of predictability in some systems. However, I’ve also been arguing that one should attempt to measure the potential predictability of the system. In this case, I think the uncertainties are pretty profound, the proposed model has zero credibility, and better models are elusive, so the tariff formula is not predictive in any useful way. We should be treading carefully, not swinging wildly at a pinata where the candy is primarily trading opportunities for insiders.

The lure of border carbon adjustments

Are border carbon adjustments (BCAs) the wave of the future? Consider these two figures:

Carbon flows embodied in trade goods

Leakage

The first shows the scale of carbon embodied in trade. The second, even if it overstates true intentions, demonstrates the threat of carbon outsourcing. Both are compelling arguments for border adjustments (i.e. tariffs) on GHG emissions.

I think things could easily go this route: it’s essentially a noncooperative route to a harmonized global carbon price. Unlike global emissions trading, it’s not driven by any principle of fair allocation of property rights in the atmosphere; instead it serves the more vulgar notion that everyone (or at least every nation) keeps their own money.

Consider the pros and cons:

Advocates of BCAs claim that the measures are intended to address three factors. First, competitiveness concerns where some industries in developed countries consider that a BCA will protect their global competitiveness vis-a-vis industries in countries that do not apply the same requirements. The second argument for BCAs is ‘carbon leakage’ – the notion that emissions might move to countries where rules are less stringent. A third argument, of the highest political relevance, has to do with ‘leveraging’ the participation of developing countries in binding mitigation schemes or to adopt comparable measures to offset emissions by their own industries.

from a developing country perspective, at least three arguments run counter to that idea: 1) that the use of BCAs is a prima facie violation of the spirit and letter of multilateral trade principles and norms that require equal treatment among equal goods; 2) that BCAs are a disguised form of protectionism; and 3) that BCAs undermine in practice the principle of common but differentiated responsibilities.

In other words: the advocates are a strong domestic constituency with material arguments in places where BCAs might arise. The opponents are somewhere else and don’t get to vote, and armed with legalistic principles more than fear and greed.