This is why Rapist Kavanaugh needed to be on the bench.
Yeah, but it didn't have to be him. I seriously doubt they'll be able to change the definition of a Citizen of the United States. If you're born here, you're American. (Also in other circumstances not pursuant to this debate.) It's not unique to America, I could probably scare up a list of similar laws around the world, but I love how he specifically says "They don't have this in Mexico.... This isn't about Mexico, but." He doesn't want to sound Racist.
I would think (IDFKNE more, with this level of corruption) it would take a Constitutional Amendment to change the definition of American Citizen. That's not the SCotUS' job, however, they can overturn it, if Congress manages to pass it. I seriously doubt that Kavanaugh is the lynchpin that would hold that together, but he could play his part. It basically takes all 3 Branches to push through something like that, and let it stand.
We all know by now that The Don lacks even a basic understanding of what citizenship involves. We knew that when he was calling Obama an immigrant. If he's spearheading this, he stands a good chance to fuck it up trying to help.