The authors of the constitution did not declare birthright citizenship to be illegal because the very concept is anathema to any coherent definition of nation or citizen.

To be clear: you think we need to choose between "everyone can pop out a kid on our soil and that kid is automatically a citizen of this country" and "you can't enforce your own laws on your own land if the perpetrator is foreign born". You think the correct interpretation of an arguably vague or ambiguous clause should result in us facing this decision.

The authors of the constitution did not declare birthright citizenship to be illegal because the very concept is anathema to any coherent definition of nation or citizen.