Yglesias contends that "essentially any able-bodied, hard-working migrant is good for the American economy":
This can be most clearly seen in agriculture. Some land in America is farmed, most is not. Much of the land is only profitable to cultivate at a wage level that few American workers find appealing. When we cut off the flow of migrant farm workers, that doesn’t magically create high-paying jobs for Americans; it leads in the short term to crops rotting in the fields and in the long term to less land being cultivated.
The land and the unskilled labor, in other words, are complements. More unskilled labor would mean more cultivated land. That would mean more agricultural output and more jobs for people who manufacture farm equipment, build food-processing facilities, or provide accounting or legal services to agricultural firms.
The Dish 