There are a couple of angles here on why a Supreme Court decision wouldn't have the final say:
It is a long stretch to argue that children born of foreign parents legally present in the country on non-resident visas have inferior claim to citizenship that those born of foreign parents illegal present, but we've seen the supreme court twists the law anyway which happens to be fashionable at the moment.
Congress does, however, have the power to reorganize the courts or to even declare certain topics such as birthright citizenship, off limits to them.
Mexico also makes it clear by what they teach in their own school classrooms that they consider the territory ceded in the Mexican War to be null and void and they encourage colonization of the area as part of a reconquest. That makes their colonization a defacto invading army.
You know I disagree with the Supreme Courts interpretation of the 14th Amendment right? I just want to clear that up because I have people coming at me as if I agree with it.
I do not believe the 14th Amendment was ever envisioned to grant citizenship to hordes of illegal aliens swarming across the border. But that is how it is being interpreted, and we don’t have the votes on the court to change that right now.
So okay, do you think Congress is going to declare the issue of birthright off limits to the Supreme Court? I mean, really, do you see that happening? Do you see the Legislative and Executive telling the Supreme Court to sod off? I’d be fine with that, but I know it won’t happen on this issue. In the absolute best of circumstances I doubt you could get even half of the Republicans to go along for political reasons.
So with that in mind the constitutional amendment is pretty much out too. What’s left? I can only see a change in the court balance reversing the birthright citizenship opinion held by the court and accepted as law by the other 2 branches of government. We’d need 4-5 of judges. That you might be able to get through if we had a large enough Senate majority to go for it (we would need a majority of Republicans that would vote for such nominees and that assumes we get rid of the filibuster for Supreme Court appointments) and the Executive branch they could simply approve the President’s nominations even if some of the judges positions weren’t popular in the polls. Basically Senators might be willing to let Judges do the proverbial “dirty work” that they’d never do themselves.
I just don’t see birthright citizenship overturned any other way. If you can see a different way of accomplishing this, something realistic, by all means tell me.