The root of that issue is that they can't work. Not legally. For all the complaints anti-immigration people make about immigrants not working, they seem to do everything they can to make it impossible to work here legally, regardless of whether you came here by foot or boat or a sponsorship.

Protectionist policies breed stagnation. Being wholesale anti-immigration in the name of protecting "our jobs" is a cover-up for preferring the comfort of not having to compete with the more skilled, more wanting, and more willing and ambitious.