Have American citizens ever tried to "check their privileges" and imagine how a life of a "visa-slave" changes after crossing the American border? I can give you some hints into my "living experience" of such a crossing.
Yesterday: an American lawyer sent some docs supporting my H1B visa over our Academy institution fax machine. The fax machine ran out of paper. The management asked me to pay for the paper, or buy them some. I couldn't afford the paper, so I borrowed $700, paid for the fax supplies and for a ticket to the US.
Today: I've got $5000 moving bonus, got $30k salary contract and got the first task, like: - We've sold something to Swedes today, you have 2 weeks to develop it. What do you need? - A Sun workstation, and an X.25 link to Sweden. - Done. And give your passport to Olga - you are going to Stockholm when done.
In 2 weeks our part was done, but Swedes were not able to finish their part and asked for 2 more weeks...
I was an employee #27, after that task and some other completed projects my salary was increased, then doubled, then again increased, then again doubled... our company went to #1 in its market, then IPOed, and 4 years after, still on the "slave" H1B visa I've found $1M on my bank account (unfortunately, it was an investment bank, lol, but that's another story).
So, my step through the US border on the H1B visa was not a step into slavery. It was liberation.