All Intensive Purposes

As quoted by DeLong, Krugman says that immigration redounds greatly to the benefit of immigrants, but very little to the benefit of everyone else ("Realistic estimates suggest that immigration since 1980 has raised the total income of native-born Americans by no more than a fraction of 1 percent."). And while there is some benefit to everyone else, the poor take a hit ("U.S. high school dropouts would earn as much as 8 percent more if it weren't for Mexican immigration").

In response, DeLong says that Krugman is "confused -- and probably wrong." Wrong how? Here's what DeLong says:

I think that we should focus on: "the net benefits... from immigration, aside from the large gains to the immigrants themselves, are small." Particularly, we should focus on the "large gains to the immigrants themselves." The net benefits from immigration including the large gains to the immigrants themselves are enormous. We shouldn't forget that.

We should be taking steps to equalize America's income distribution: more progressive tax brackets, more public provision of services, a more generous Earned Income Tax Credit, a higher minimum wage, a greater focus on education. But tight restrictions on immigration are a really lousy anti-poverty policy: one with enormous excess burdens measured in money, and truly mammoth excess burdens measured in utility.

So where is Krugman "wrong"? They disagree on the question of whether you run social policy in this country for the benefit of those who live here or those live here and some others who might come to live here as well -- but there is no right answer to this question. It's hardly unreasonable to start from a baseline in which the government acts for the benefit of its own citizens. DeLong wants to suggest that "right restrictions on immigration" are something the poor need to purchase, and he measures their cost as if it's something the poor need to buy from foreigners as well. Free trade is a choice, not a state of nature. If you start from the presumption that social policy ought to benefit the poor, and then ask what we pay them to take the wage hit that comes with open immigration, I think you'd end up with a different policy. If the more affluent want the benefits of immigration, let's find a way to leave no one worse off.

If empirical testing of my hypothesis is necessary, I stand ready to receive chocolate bars.