… is from page 205 of William Easterly’s 2013 book, The Tyranny of Experts (original emphasis):
The nationalist obsession also blinds us to positive effects of migration on global development. When a Haitian moves from a place where she earns little to a place where she earns much more, she has increased global GDP. Why should we care only about national development and not about global development?
Even a hyper-nationalist (that is, one who puts absolutely no value on the welfare of foreigners) can accept the relevance of Bill’s point – assuming that that hyper-nationalist understands economics. Such an American hyper-nationalist would understand the fact that more immigrants into the United States over time increases the economic welfare of Americans. (This hyper-nationalist, by the way, would understand also that free trade has the same happy effect on Americans’ economic welfare.) He understands this economic reality because he knows that a larger labor supply means greater (and, hence, more productive) specialization and a greater supply of human creativity. Such creativity, in a free society, is the key input into entrepreneurial innovation.
This economically knowledgeable American hyper-nationalist would further understand that any change in resource allocation – including the allocation of labor – that reduces the costs borne by American firms of producing goods and services contributes to the long-run growth of the American economy. If a Haitian can produce an hour’s amount of lawn-mowing at half the cost of an American, the American loses his job mowing lawns. The lower-cost input (the Haitian) replaces the higher-cost input (the American) while the amount of lawn-mowing supplied to American homeowners and businesses increases. It increases because, with the price of lawn mowing now lower, Americans purchase more of it.
The American’s wage to mow lawns is twice that of the Haitian’s because the opportunity cost of the American’s time spent mowing lawns is twice that of the Haitian’s. If, by the way, the American’s lawn-mowing wage was significantly higher than this American’s opportunity cost of mowing lawns, then not only were some other Americans unnecessarily suffering by paying excessively high prices to have their lawns mowed, but also the the total economic output in America – which the hyper-nationalist American presumably cares about – was lower than it would have been had the American’s wage reflected his opportunity cost of mowing lawns.
When the American loses his lawn-mowing job, he is freed up to produce what he would otherwise have produced, but didn’t, when he was occupied mowing lawns. Not only do we Americans get more lawn mowing as a result of the Haitian’s immigration to the U.S., we get also whatever additional goods or services are now produced by the American who formerly was employed mowing lawns.
Yes, yes, yes: the above process takes time. It causes displacement of workers, which is often painful to the workers who are displaced. But just as there is nothing unique about international trade in causing economic churn, there is nothing unique about immigration in causing economic churn. Put differently, if you believe that protecting the American from losing his job mowing lawns is a sufficient reason to restrict immigration, then you must also believe that protecting the American from losing his job mowing lawns is a sufficient reason to outlaw American homeowners from choosing to spend more of their time mowing their own lawns rather than hiring workers to do the mowing. Unless you’re willing to enforce this latter restriction and countless others akin to it, then you’ve no good economic reason to oppose immigration.
