That is very true, which is why the Court in 1884 ruled the status of the parents of a child born within the territory of the United States determines whether or not the child is eligible for U.S. citizenship. It is their allegiance to the country that matters, not their kid's.
But the real acid test is this: the 14th Ammendment's primary purpose, the fundamental reason it was adopted, was to make citizens out of those who had been slaves, who had not legally been citizens before the adoption of the Ammendment.
Absolutely, that was what the 14th Amendment's original intent was, to give legal status to the former slaves and their offspring. Foreigners were not part of the deal, the framers of the Amendment said as much and the Court of 1884, which has yet to be overturned correctly interpreted it.
If we interpret the Ammendment to mean that only the children of citizens become citizens, then the Ammendment cannot have the intended effect, because the slaves were not the children of citizens.
Not really because with the ratification of the 14th Amendment former slaves were granted citizenship, which means their kids would fall under the automatic citizenship clause. Legal immigrants who swear an oath of allegiance to the country and become citizens are also included. The Supreme Court ruled that way in United States v Wong Kim Ark of 1898 and it still stands to this day.
That's absolutely not correct. Wong's parents specifically did not owe the US allegiance, but were here temporarily. At the time, Chinese immigrants were forbidden from ever applying for citizenship, under the Chinese Exclusion Act. The Wong decision was based not on the allegiance of the parents but the simple fact that they were resident, not diplomats, not "Indians not subject to taxation," and not part of an invading army.
The bottom line is that SCOTUS isn't going to give you the answer you want. Wong makes the citizenship aspect Hamdi's case open-and-shut: Wong's parents were here every bit as temporarily as Hamdi's, so Hamdi is a US citizen. (He may still lose his case, but it will be due to the government's argument, not FILE's.) And there's no chance at all SCOTUS will overturn Wong.
The very best you can hope for is that Rehnquist can steer the majority away from the issue of illegal aliens altogether. At worst, Wong will be confirmed and extended to cover illegal aliens. Anyone who thinks a majority of this Court is eager to revoke the citizsenship of a million Hispanic children is a fool.
How does the language of the 14th Ammendment bestow citizenship upon the former slaves? It nowhere says "all those who used to be slaves are hereby granted citizenship." All it says is the following:
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.
No interpretation of those words that does not obviously bestow citizenship on the former slaves can possibly be valid. The interpretation that requires that only the children of citizens become automatic citizens by birth fails to do that, and is therefore provably incorrect.