A Profession With an Egalitarian Core: ...A distressingly large portion of the debate in many countries analyzes the effects of higher immigration on domestic citizens alone and seeks to restrict immigration to protect a national culture or existing economic interests. The obvious but too-often-underemphasized reality is that ... immigration could create tens of trillions of dollars in economic value, as captured by the migrants themselves in the form of higher wages in their new countries and by those who hire the migrants or consume the products of their labor. ...
In any case, there is an overriding moral issue. Imagine that it is your professional duty to report a cost-benefit analysis of liberalizing immigration policy. You wouldn’t dream of producing a study that counted “men only” or “whites only,” at least not without specific, clearly stated reasons for dividing the data.
So why report cost-benefit results only for United States citizens or residents, as is sometimes done in analyses of both international trade and migration? The nation-state is a good practical institution, but it does not provide the final moral delineation of which people count and which do not. ...
Economics evolved as a more moral and more egalitarian approach to policy than prevailed in its surrounding milieu. Let’s cherish and extend that heritage. The real contributions of economics to human welfare might turn out to be very different from what most people — even most economists — expect.
I can understand why it might have been advantageous from an evolutionary perspective for nature to make us care most about those who are closest to us.
It seems like there are two ways to get beyond this tribalism. The first is to expand the definition of the tribe to include everyone. According to the column, and to economic theory and evidence more generally, open borders don't just benefit immigrants, they help everyone. Since immigrants benefit us all, the definition of the tribe should be expanded to include them. The second, which is also in the column, is to argue it's a moral issue. We can and should grow beyond the tribal instincts that lead to war and other problems, forget about borders of all types as a distinction for measuring costs and benefits of immigration, and treat everyone the same.
Under the first approach, we care about people based upon what they can do to help us. Under the second, which I prefer, we care about people simply because they are people.