Studly, you said, "I cannot see how any Asians, Russians or Europeans have snuck across our border, unless it's through Canada or Mexico."
Well, this will interest you, then, and we have the same problems up here in Canada.
Enjoy! (you won't)https://ca.news.yahoo.com/federal-agents-target-industry-helps-chinese-women-american-171427338.html
On another front, our own CONSERVATIVE feds with their temporary foreign worker program has has had some interesting exposure as well. It appears the 'let business police themselves small gov't after all' has come back to bite them in the ass. Apparently, when their (temp workers) work visas and temp jobs ran out or finished, NO ONE was checking to see if they left the country, rofl!