I still disagree with the decision. Not necessarily with the natural law aspects, but rather that I agree with Mr. Jackson's comment about "sheltering under the shade of the British king". Smith reached the age of 18 years in 1776, yet did not return to America until 1783, after the war had ended. I guess that didn't qualify as "some neglect or overt act" as Madison put it.
I have to wonder if my hardscrabble Scots-Irish ancestors of South Carolina, who stood and faced those British bayonets, would have agreed with Mr. Madison.
All we have is the testimony of the members of Congress at the time. And Dr. Ramsay's argument against Smith was theoretical, as far as I can tell, and not based on any specific reasons to doubt Smith's allegiance to the US.
But that's all beating a dead horse. What matters now is the way the Founders conceptualized the issues of citizenship, not whether they may have been mistaken in their application of them to a particular case.