Birthright Citizenship: What's the Worst That Could Happen?

The US Constitution says, in the 14th Amendment, "All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside."

Just after he was inaugurated in 2025, Donald Trump issued an executive order that denied citizenship to persons born from a mother who was unlawfully present in the United States and the father was not a U.S. citizen or lawful permanent resident. Since these two documents are in opposition, it went to the courts, and is now in front of the Supreme Court. 

Trump issued the order to make it easier to deport people, but the implications go much further. If a birth certificate doesn't guarantee citizenship, what does? This opens up an avenue for questioning the rights of anyone you want. Imagine someone made Trump mad (as often happens). An investigation can be opened on their right to live in the US. 

Are you an American citizen? Yes, I was born here. 
But were both your parents American citizens. Yes, they were born here, too. 
But were they born to American citizens? Yes, my grandparents were all born here.
How about your great-grandparents? They immigrated from Europe and became American citizens. 
They legally became American citizens? Prove it. 
  
Anyone who immigrated to the US before 1906 may have a hard time proving it, especially if their citizenship was derived by relation to a head of household. And citizenship documents were rarely archived for posterity anyway. The 14th Amendment is there for a reason. If it is not upheld, we could theoretically turn half our citizens into stateless people. Only immigrants who were naturalized or those who had ancestors with acceptable documentation (and possibly Native Americans) would have the right to vote.