I'd advise a bit of caution when talking about this. I certainly don't know everything there is to know about hiring foreign nationals, illegals, US citizens, etc. For instance, in this thread, we've said:
- You cannot discriminate against a person based on National Origin.
- You must first offer a job to a US citizen.
I also know that, regardless of visa type (or even if a US citizen), you often have to run a check through E-Verify to ensure that someone is employment-eligible.
My point is that there are a LOT of laws and loopholes. Very often, there is no "absolute" right or wrong. Just a whole lot of "may" based on criteria A, B, and C. I'd just caution against making blanket statements (that goes for me, too - since I do it occasionally).