The short answer is that there is no difference between a worker with a skill that's not in demand and a worker with no skill at all. We got lots of good steelworkers in this country, but most of 'em aren't in the steel biz anymore.
The offshoring trend is making people with college degrees and good employment track records in computer science and engineering into people with skills that aren't in demand anymore. These people now become indistinguishable from an illegal alien picking crops...except the illegal has a job.