The language isn't ambiguous as the authors of that language tell you exactly what it means.
"Not owing allegiance to anybody else. That is what it means."
What many folks think it means, and what it actually means, are two different things. The only reason for that is ignorance of the topic.
This is Senator Trumbull the author of the language inserted into the 14th's citizenship clause.
The provision is, that 'all persons born in the United States, and subject to the jurisdiction thereof, are citizens.' That means 'subject to the complete jurisdiction thereof.'
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What do we mean by 'complete jurisdiction thereof?' Not owing allegiance to anybody else. That is what it means.
The Congressional record proving that.
A close up for those who may have trouble reading the small print.
This Senator Howard, the author of the 14th.
I concur entirely with the honorable Senator from Illinois [Trumbull], in holding that the word "jurisdiction," as here employed, ought to be construed so as to imply a full and complete jurisdiction on the part of the United States, whether exercised by Congress, by the executive, or by the judicial department; that is to say, the same jurisdiction in extent and quality as applies to every citizen of the United States now.
The Congressional record proving that.
A close up for those who may have trouble reading the small print.
They didn't mean something other that what they said it meant.
And what they agree they meant is the following.
A full and complete jurisdiction that meant,
Not owing allegiance to anybody else.
This is a definitive. There is no rebuttal to it.