DeLong concludes with a reasonable demand:

[T]he thing to object to in the turn this entire debate has taken has been the failure to focus evenly on the consequences for all stakeholders in global migration–look at what happens to everyone, not just one particular group that is convenient for your current political position.

But a paragraph earlier, he supplies what he’s shopping for:

[I]ncreased immigration is very good for new migrants, good for savers worldwide, good for native-born workers, good for previous immigrants who have substantially assimilated–social knowledge, English proficiency, et cetera–and probably bad for previous immigrants who have not assimilated.

Yep. And when you remember that a lot of previous immigrants want to bring over family members, even the last one’s not so clear. Foreign economists have hurt my income, but I’m glad to have them here; to me, they’re family.