…Arthur even refrains from making comments on English home affairs–the Irish rebellion, for instance, which is agitating millions of American citizens, who are also born Irishmen like the President.
http://www.obamaconspiracy.org/2009/04/chester-a-arthur-rest-in-peace/
Question: If Arthur's eligibility was questioned at the time, why wasn't the Constitutional meaning of Natural Born Citizen defined by law then?
A few questioned his place of birth. Donofrio showed this via newspaper records from the time. IIRC, nobody questioned the fact that his father was a foreign national when C.A. was born (I would assume because nobody knew his fathers status at the time or had reason to question it), who didn't become naturalized till C.A. was 14 y.o.
As far as why didn't they define the term then...that is a question for those around at the time. I would assume because the general public at large were unaware there were questions surrounding C.A. eligibility. Therefore, there was no need at the time.
One could be born an Irishman, and still be born in the US, of parents who were US citizens. Since Arthur's mother was born in the US, and thus a citizen, and his father was a citizen by the time he became President, no one thought to ask *when* his father became a citizen. As it turned out it was 14 years or so after Chester's birth.
Being an Irishman can be just a state of mind. Lots of Irishmen fought for the Union, and for the Confederacy. Their grandchildren often still thought of themselves as Irish. (I had an Uncle, by marriage, like that He was James, his brother was Patrick, they went to St. Patrick's church) He would have been born around 1910 or so, but it wasn't in Ireland, but rather in Nebraska, and I don't think his father's birth was either. But he could turn on that brogue at will.
I once knew a guy, a least third generation US citizen, that spoke with a German accent. Dude looked like slightly taller and think Hitler. He was President of the campus Young Americans For Freedom. The father of my doctor, was a south Texas Rancher, who would not speak English in his home, although outside it, he could speak it just fine.)
Being Natural Born doesn't completely guarantee one would not have sympathies for a foreign nation or people, but making that a requirement for eligibility to the office of President was about the best they could do.
Because it was unnecessary since the definition had been well known in common law as the Court in Minor versus Happersett noted when it quoted the definition again as the Court in The Venus case of 1814 had quoted it:
"The natives, or natural-born citizens, are those born in the country, of parents who are citizens."
And that definition has never changed.