President Trump's policies are a rich field for sowing evidence on the application of the law of unintended consequence in economic policies. Take his Trade War with China that so far resulted in ca USD20 billion in fiscal receipts and USD26 billion payouts in subsidies to U.S. farmers, netting a fiscal loss of USD 6 billion (https://trueeconomics.blogspot.com/2019/06/17619-lose-lose-and-lose-some-more.html), while generating gains for European exporters (https://trueeconomics.blogspot.com/2019/08/15819-winning-trade-wars-round-3.html) and shrinking net real exports for the U.S. economy (https://trueeconomics.blogspot.com/2019/08/1919-losin-spectacularly-trump-trade.html) and driving losses to the U.S. exporters (https://trueeconomics.blogspot.com/2019/07/31719-fed-rate-cut-wont-move-needle-on.html). Another example, the never-ending rhetorical and regulatory war against skilled (and other) migration.
On the latter, we have plenty of evidence drawn from Mr. Trump's predecessors that conclusively shows the costs of severely restrictive application of the skills-based migration quotas. And, thanks to Mayda, A M, F Ortega, G Peri, K Shih, and C Sparber 2017 paper, titled “The Effect of the H-1B Quota on Employment and Selection of Foreign-Born Labor” (NBER Working Paper No. w23902, https://www.nber.org/papers/w23902.pdf), we now have an in-depth analysis of the mechanics by which unintended consequences of restricting skilled migration impose these economic losses on the U.S.
The authors looked at how changes in H-1B policy, enacted over the years, affect the characteristics of migrants entering the U.S. and how these changes alter U.S.-wide productivity and wages.
Per authors, "The economic intuition [behind the study] is simple. Firms across the globe compete to hire highly skilled workers. The strict quota and the lottery allocation generate uncertainty in acquiring the legal right to work in the US even after securing a job offer. Hence, talented foreign nationals might elect to work elsewhere. Similarly, US firms face uncertainty over whether they will be allowed to employ the top job candidates they have identified. Some firms might elect to forgo this uncertainty altogether by turning to alternative labour sources."
"First, we examine H-1B quality. ... ...H-1B restrictions have particularly hindered the employment of the highest ability foreign-born workers. Anyone who believes immigration policy should be designed to attract ‘the best and brightest’ workers to the country should be troubled by the discovery that restrictions to aggregate inflows generate the opposite effect. Quantitatively, the number of new H-1B workers from the highest wage quintile is nearly 50% lower than it would have been in the absence of H-1B restrictions, but the number of new H-1B workers in the median wage quintile is unchanged." In other words, if wages are a proxy for talent, skills and productivity, reducing H1B quotas appears to reduce availability of more skilled, more talented and more productive foreign workers, while having zero impact on availability of mid-range skills, talents and productivity workers.
Worse, reduced H1B quotas also increased concentration of H1B attaining firms (or reduced the pool of employers with a meaningful access to H1B workers). Authors conclude that "It is possible that when faced with the uncertainty and costs of the H-1B hiring process, economies of scale and network externalities arise that favour firms specialising in H-1B employment and workers with specialised knowledge about the legal hiring process." Or put differently, H1B quotas restriction may be fuelling increase in the share of foreign talent brought into the U.S. by outsourcing agencies and a handful of very larger employers. This selection bias does not appear to be linked to higher productivity and is, therefore, welfare reducing as compared to a system where firms that can generate higher productivity increases by employing foreign workers gain better access to H1B via markets.
In summary, "we presume that by reducing the H-1B cap from 195,000 in 2001-2003 to 85,000 today, policymakers intended to reduce new H-1B employment at for-profit firms and possibly increase employment of competing US-born workers. The policy achieved the first but not the second goal. Moreover, the cap restriction also generated consequences that were likely unintended. The policy change has particularly deterred workers with the highest earnings potential from entering the US labour market. Given the potential for productivity-enhancing technological gains generated by H-1B workers, this loss could reverberate throughout the economy. Other important effects are distributional and favour computer-related occupations and firms that use the H-1B programme heavily."
Consequences. A lesson for MAGA crowd from their predecessors.