Distrust immigration studies

Economics prof. Steve Landsburg is radically pro-immigration, and argues that is the only morally and economically correct policy here and here.

I posted this comment on his blog, but it was deleted:

Steve, anytime you start saying things like “$3 worth of benefits to Americans”, you are making politically loaded statements that conceal dozens of dubious hidden assumptions. It is like saying, “re-electing Obama will cost you $10,000?. Such a statement is not a fact, but a reflection of the opinions of the speaker.

As I see it, these bogus immigration economics studies come from (1) immigrant communities who want to bring in their friends and relatives, (2) businesses who want the cheap labor, (3) libertarians who want to bankrupt the welfare system, and (4) leftists who want to undermine the American political system. No, I do not accept any of their figures unless they are demonstrably free of those biases.

I am posting here just because it was deleted there.

I often hear people say that without our immigration policy, food would cost twice as much, or the web would not be searchable, or some other such nonsense. American immigration policy has huge costs that should be obvious.