Thus, Vattel is clearly admitting the English practice as entirely valid and is no way insisting that the new United States of America was obligated to adopt any other manner of declaring who was a citizen at birth than that already in use. Sure, naturalized at birth is a possibility, though it does not equal natural born. We might as well throw in the next section, too:
§ 215. Children of citizens born in a foreign country. It is asked whether the children born of citizens in a foreign country are citizens? The laws have decided this question in several countries, and their regulations must be followed.(59) By the law of nature alone, children follow the condition of their fathers, and enter into all their rights (§ 212); the place of birth produces no change in this particular, and cannot, of itself, furnish any reason for taking from a child what nature has given him; I say "of itself," for, civil or political laws may, for particular reasons, ordain otherwise. But I suppose that the father has not entirely quitted his country in order to settle elsewhere. If he has fixed his abode in a foreign country, he is become a member of another society, at least as a perpetual inhabitant; and his children will be members of it also. So, applying §214 to Obama, he could be naturalized by the U.S. However, according to §215, British law would also make a claim on Obama Jr. as a child of a citizen born in a foreign country, of which Vattel says "their regulations must be followed". If both the U.S and Great Britain are applying the same law, then the Obama could have naturalized at birth, but he was still, legally, a British subject.
Sounds like a turf war; I say we concede this round and let the Queen keep him ;-)