[coldtea]

>And in most scenarios when I've had to argue against isolationists they tend to ignore issues such as Americans refusing to work in certain labor sectors that illegal immigrants tend to work

Well, that's a question of payment. Raise the salaries, and Americans will flock to those sectors. Instead of artificially keeping the margins up and the salaries low through labor import (which would end to the lowest common denominator race to the bottom among world economies, but usually it stops midway just lowering the options for the higher economies).