Congress is given the authority to define naturalization.
"The Congress shall have power ... To establish a uniform rule of naturalization...."
The idea of birthright citizenship is naturalization by a law made by Congress and could be undone by Congress.
Birthright citizenship came to the colonies via English common law. Upon achieving statehood, the new states adopted the English common law on citizenship. Under the Constitution, birthright as stated in English common law continued. With the 14th Amendment, birthright citizenship was placed beyond the reach of Congress, and the words used were, "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." The Congress only has power to pass laws consistent with that.
This is incorrect, and I can prove it!
The State legislature of Pennsylvania ordered the Pennsylvania Supreme court to determine what English Laws were still in effect in Pennsylvania. The Court delivered it's report to the legislature. Among other English laws they determined were null and void, they determined that Citizenship did not come from English common law, but was instead descended from the natural law principles articulated by Vattel.
Here is the relevant page of their report.
And as it should happen, some of *THESE JUDGES* were present and involved in the constitutional process.
I will also point out that the Constitutional Convention was held in Philadelphia (at the legislative house, otherwise known as "Independence Hall".) and if *ANYONE* knew what was the intended meaning of "natural born citizen", it would be the Philadelphia Pennsylvania legal community.
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