Exactly- would everyonr have to take special steps to prove that your child is an American citizen at birth? How you determine whether someone's parents were here legally or illegally? Do we really want situation where an adult who believes he or she is a citizen finds out they are not a citizen because of some glitch in their mother's visa during birth?
You seriously don't think there is a difference between a documented LEGAL immigrant and an illegal immigrant? How does one prove their parents were here legally? No one is talking about making this retroactive.
This isn't about curbing LEGAL immigration, it's about the rights of LEGAL citizens, alien or native, IMHO.