I appreciate your research to verify that ALL citizens-at-birth qualify as “natural born citizens.”
Its really very, very simple: if you are an American citizen but not a naturalized citizen and therefore ineligible to be president or vice president then you are a citizen-at-birth and you qualify to be president or vice president as a natural born citizen.
A person who was in one of those seven categories of citizens-at-birth that you named was Charles Curtis, the 31st Vice President of the United States who was the first person with acknowledged Native American ancestry to reach either of the two highest offices in the United States government’s executive branch. His maternal ancestry was three-quarters’ Native American, of ethnic Kaw, Osage and Pottawatomie ancestry. Curtis spent years of his childhood living with his maternal grandparents on the Kaw reservation.
The fact that Barack Obama is President of the United States and that John McCain COULD have been president of the United States is verification of the above.
The national Republican Party, the McCain-Palin campaign and all of the Republican attorneys in the House of Representatives and the US Senate would have never allowed Obama’s elevation to the presidency without a legal challenge if what I have stated was untrue. Nor would the US Supreme Court have rejected all Obama eligibility challenges from being heard if there were constitutional grounds to disqualify him.
My research, as you term it, verified that not all citizens at birth are natural born, nor even native born. Some are, for Constitutional purposes, naturalized at birth. This is sometimes referred to as "acquiring" citizenship at birth, but only to distinguish it from individual naturalization of persons originally holding foreign citizenship. But since Congress has no power over citizenship other than via establishment of a uniform rule of Naturalization, anyone who "acquires" citizenship via a statute, must be considered "naturalized" for Constitutional purposes.
Charles Curtis was born in the US, was he not? Of parents who were citizens?
McCain would have qualified because he was born of two citizen parents, and "in the armies of the nation". Parents who have children while serving outside the country are deemed not to have left it's jurisdiction, and those children are deemed "born in the country". See Vattel, Book I, section 217.
Nor would the US Supreme Court have rejected all Obama eligibility challenges from being heard if there were constitutional grounds to disqualify him.
None were rejected on Constitutional grounds. The lower court cases were rejected on "standing" and "justicibility" grounds, while the Supreme Court never gives a reason for not hearing cases, so you can't make any conclusions from their doing so, nor does it create any precedent.
As to the Republican Party and the McCain Campaign, they were likely afraid of being termed "racist".
Sarah Pallin states in her book that she wanted to go into Obama's background, associations and so forth (but not specifically eligibility) but the McCain campaign would not let her. If they wouldn' let her talk about Bill Ayers or Rev. Wright, they sure as heck weren't going to even look at the eligibility of the first Black (well half Black) major party candidate for President. Wouldn't have been politically correct.