Well then it's you who is confused, since all I said was that most Americans don't believe that. Whether it's true or not, I've not seen any data. Your view appears to be in the minority.
Perhaps you will prove that illegals are not taking any jobs from Americans.
As I'm sure you are aware, when one makes a specific charge, it is not up to everyone else to prove him wrong, it is up to him to prove his charge correct. Again, I can't say one way or another, but I can say that most Americans don't believe that.