At RealClearMarkets David Hebert makes the case against tariffs, largely a response to Oren Cass’s defense of Trump’s plans. His arguments generally follow the standard neo-classical arguments with a soupçon of ad hominem tossed in:
Oren Cass has written several articles about the need for tariffs to save America. Like all his writings on this subject, he reveals that he has learned enough economics to be a nuisance but not enough to be helpful. In them, he accuses economists of only thinking about the costs of tariffs, such as the increased prices, the net loss of jobs, stagnated economic progress, and the retaliatory tariffs which other nations levy against America, which cost us dearly. At this point, anyone following his work can be left with but one conclusion: he will not let facts stand in the way of his agenda. While his tenacity is admirable, his economic prowess is not.
In these articles, Cass commits three fundamental errors: 1) a misapplication of what economists call “externalities,” 2) falling victim to the water-diamond paradox, and 3) a disregard of secondary effects.
I’m not arguing against him because I largely agree with him but I wanted to address some specific points that Dr. Hebert makes and explain where I differ from him.
By allowing innovations, even those from abroad, to proliferate in the American economy, new jobs that were previously unimaginable are created. In 1900, for example, there were no pediatric oncologists. Today, there are over 2,000.
This is a very complicated subject, too complicated for a blog post. First, people who work in the healthcare sector are compensated based on how much care they provide not based on how much health they provide. Now specialization is a necessity as the absolute amount of knowledge increases but it is also aligned with the incentive to provide more care.

From 1900 to 2000 life expectancy (a reasonable enough proxy for health) grew considerably but starting around 2005 that peaked and, indeed, has actually decreased in recent years. Some but not all of that decrease was due to COVID-19. Some was due to bad habit but I believe that some was a result of increased care having a limit in its marginal productivity. At this point while I think there’s a good argument that different care could produce additional benefits I don’t think the argument that more care will is quite as good as it used to be.
I suspect that here Dr. Hebert is succumbing to the flaw he criticizes—failure to consider marginal benefits. Does one more pediatric oncologist actually produce more health?
Equally impressive, in 1900, almost 40% of the American working population was employed in agriculture. Today, that number is less than 2%.

I’m going to use wheat production as a proxy for agricultural production here. As you can see from the graph above a decreasing number of people working in agriculture were able to produce an increasing amount of wheat. Until 1980 that is. What happened?
I don’t know. You tell me. I can think of all sorts of explanations but what happened is hard to argue. Starting around 1980 U. S. wheat production went flat (noisy but flat) and has remained so. My key point: production is how much wheat you are producing. I suspect that globalization played a role.
This post is starting to get long and I have several additional points to make. I’ll be as terse as I can. I understand comparative advantage but there are three problems. I have yet to meet a CEO who understands comparative advantage or one who does not understand absolute advantage. Chinese has an absolute advantage over the United States on a very wide array of manufactured goods. Under the circumstances comparative advantage makes little difference. And the Chinese leadership has sufficient authoritarian control to limit imports and regulate prices to give China comparative advantage as well as absolute advantage.
As I’ve said before I think that China is a special case and we have little recourse but to impose tariffs on China.
Finally, I think that Dr. Hebert is engaging in a certain amount of hand-waving. Consider the Bureau of Labor Statistics’s list of fast-growing occupations. Some don’t pay enough to maintain a middle class lifestyle (home health assistants and veterinary assistants); some are highly subsidized (wind turbine service technicians, solar photovoltaic installers); and some require qualifications that relatively few can satisfy (veterinarians, physicians assistants, data scientists). Every single one of them is tertiary production.
I think we need more primary and secondary production. Does Dr. Hebert believe we can support the American population based on tertiary production alone?






