In June, Representative Mo Brooks took the opportunity to model constructive and reasoned disagreement in his responsetoan article in which I criticized his and Senator Jeff Sessions’ stances on immigration. On Labor Day, Senator Sessions claimed that unemployment and labor force participation statistics make the case for continuing American restrictions on low-skill immigration. With Congress set to take this up again next week, it’s a good time to reexamine the evidence. Unfortunately, there is still more fear than fact in the case for restricting immigration.

The most credible evidence published in scholarly economics journals suggests that immigrants are either a net benefit (the optimistic case) or “essentially a wash” (the pessimistic case) for the American economy. In a 2011 paper for the Center for Global Development that was ultimately published in the Journal of Economic Perspectives, Michael Clemens summarized the literature on immigration. He referred to the potential benefits of more open borders as “trillion-dollar bills on the sidewalk” and pointed out that “the estimated gains [from dropping barriers to labor mobility] are often in the range of 50-150% of world GDP.” The World Bank reported that World GDP in 2011 was about $70 trillion, which means dropping barriers to labor mobility could increase the size of the world economy by $35-$105 trillion dollars. That’s a lot of new wealth in the pockets of American residents and our potential foreign customers.

Here is Clemens’s summary of the most credible evidence on immigration’s effects:

“[A]ll serious economic studies of the aggregate fiscal effects of immigration have found them to be very small overall—small and positive at the federal level…small and negative at the state and local level.” He continues: “In historical cases of large reductions in barriers to labor mobility between high-income and low-income populations or regions, those with high wages have not experienced a large decline.” Again, there is some evidence that wages fall slightly for people at the top and bottom of the skill distribution, but the long-run effect on native wages overall is either zero or positive.

In his essay “What is Seen, and What is Not Seen,” Frederic Bastiat cautioned us to count costs and benefits accurately. In Economics in One Lesson, Henry Hazlitt stated Bastiat’s lesson as follows: “The art of economics consists in looking not merely at the immediate but at the longer effects of any act or policy; it consists in tracing the consequences of that policy not merely for one group but for all groups.” This makes it easier to see that immigrants don’t “take our jobs.”

Claiming that every job held by an immigrant is a job that would have gone to an American is a mistake. A lot of Alabamians hire house cleaning and landscaping services or eat more restaurant meals because immigrant labor makes these services more affordable. Many of these jobs wouldn’t exist if immigrants weren’t here to do them at prices native-born Americans find attractive.

Representative Brooks is right that Alabamians worked in construction and poultry processing before immigrants arrived. How competitive would these industries be if immigrants weren’t here? People hire less if labor is more expensive. People build less when it is more expensive to build. We’ll either eat less chicken or import it from other states and abroad if we make it more expensive to process chicken in Alabama.

Immigrant labor means cheaper chicken, and this lowers costs for chicken users. Just because Bob lost his job at the poultry plant doesn’t mean immigration hurts Americans generally. What’s harder to see is that lower-cost chicken processing makes it easier for people who sell chicken to expand.

This creates new opportunities for store managers, cashiers, bookkeepers, and others. There are exceptions, but these jobs are likely to be filled by Americans because they are likely to require more language skills. Working a fast food cash register may not pay as well as gutting chickens in the short run, but it’s almost certainly much easier on the body, I suspect the work environment is safer and more pleasant, and there are almost certainly more advancement opportunities.

Arguments that immigrants burden the welfare state undermine the case for the welfare state, not the case for immigration. Representative Brooks wants “an immigration policy that selects for immigrants who “are most likely to be net tax producers, not net tax consumers.” So let’s make it harder for people to consume taxes. With respect to immigration, let’s allow anyone who wishes to move here with the provision that they are ineligible for tax-funded government benefits. Presto: armies of foreign-born “net tax producers.”

Keeping immigrants out will also cost us liberty as well as money. What invasions of privacy are we willing to countenance in order to prevent people from living and working here? We’re slowly and steadily crushing businesses under ever-heavier regulatory burdens. What will happen when we tell them “here’s a new stack of immigration rules”?

Immigration restrictions might be good populist politics, but they are lousy economics. As Julian and Rita Simon noted in their contribution to the 1993 book Second Thoughts: Myths and Morals of U.S. Economic History, some of our Founding Fathers recognized this over two centuries ago. They quote James Madison’s statement at the 1787 Constitutional Convention: “That part of America which has encouraged the foreigner the most has advanced the most rapidly in population, agriculture and the arts.” If we want a brighter future for our children, it’s a lesson we should take to heart.

Note: Readers may also be interested in this month’s feature essay on immigration from the Library of Economics and Liberty, where I also blog. I wasn’t paid for mentioning the immigration essay or the blog in this article.