Should High Worker Wages Be a Problem?

David Frum argues that a guest worker program would pose a threat to the economic revitalization of the working and middle classes:

The immigration debate is often premised on the assumption that high wages for American workers are a problem to be overcome. If you'll look again at the Cleveland Fed chart above, you'll notice that the collapse in labor's share of national income coincides with the start of the mass immigration influx after 1970. Since then 40 million people have migrated to the United States, most of them very low-skilled. About one-third that number arrived illegally.

Immigration advocates insist that this huge surge of cheap labor has nothing to do with the persistent decline in wages that began about the same time. If so, that's one hell of a coincidence. With President Obama proposing accelerated flows of immigration in future, American workers should ready themselves for more coincidences ahead.