"No. I think we can maintain a good idea of what kinds of jobs Americans want to work and what we're unwilling to."
Go ahead: Name some of those jobs that Americans are unwilling to work.
Domestic servant
Farm worker (picker)
Some janitorial jobs (office cleaning, etc.)
Bussing and dish washing in cheap eateries
Harvesting pine straw. Working in the ferneries. Two local examples of jobs that simply cannot get local workers and have to rely on Mexicans. They're both basically "stoop labor" jobs, and Americans are no longer willing to do that kind of work.