Many of the illegal immigrants are brought here essentially for slavery.
Our politicians are rather schizophrenic in this matter. On the one hand, as a member of the military, I have had to take a class on how to recognize human trafficking and what to do about it. OTOH, they turn their backs on illegal immigration which feeds the problem in the US and refuse to do anything about it.
Human traffickers take advantage of lax immigration laws. They do the same thing in Europe. The sex trafficking business exploded in Europe when the European Union went into full effect because it decreased border enforcement.
This is one of the problems that wont be solved until nations get a handle on their borders. It’s just like drug trafficking...we are fighting a losing battle because we refuse to confront the real source of the problem.