[bushpilot1]

It is possible the author means..Polk was the first President born to US citizen parents after the ratification.

[UnbelievingScumOnTheOtherSide]

It is possible the author means..Polk was the first President born to US citizen parents after the ratification.

The inferrence I drew from the question was that an Obama born in Kenya would somehow equate to the first 10 presidents in not being born in the "United States". I wanted to emphasize that was not the only qualification in the Constitution.