Because it was redundant. If they viewed it as a source of confusion or error, they would have done more than simply omit the words, they would have rectified the situation. Either you are born a citizen, or you are not. There is no "born a citizen but not a natural-born citizen" third type. And if you want to drop names of Founders to support your claim, remember, there were Founders in Congress in 1790, too, and some guy was President then... Oh, yeah, that would be George Washington!
Additionally, the 1790 act was a naturalization act. How could a naturalization act make anyone an Article II "natural born Citizen?" After all, a "natural born Citizen" was made by nature at the time of birth and could not be so made by any law of man.
Yet you feel you can just make up new definitions and misquote and cherry pick rulings to support it? Where are the footnotes in the Constitution pointing out the citations of Vattel? You are basing your argument on half-definitions and the opinion, clearly identified as such, of the author of a book never cited by the Founders. It was just one of many sources utilized, and never cited. Blackstone is also cited in SCOTUS cases, even more frequently, was and has been a standard legal reference even into modern times, and it says something entirely different. So your non-cited, non-founding document is entirely irrelevant because the Founders said nothing whatsoever about the birthplace, but only about the status at birth, which, like it or not, it leaves to Congress to decide. Just like in the Federalist Papers, where multiple sides of the debate are presented, only one was ultimately included in the Constitution.
You are simply wrong, and stuck in your little memeplex. Good luck with that.
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