The issue is confused anyway. The law about parents and natural born citizen applies to people who want natural citizenship, but were born outside the country (IE parents had an early child unexpectedly on a cruise or vacation or something). Obama was born in the US, so he is granted natural born citizenship solely on that.
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Relevant passages:
snopes said:
The item quoted above posits that Barack Obama does not qualify as a natural-born citizen of the U.S. because the law in effect at the time he was born specified that "If only one parent was a U.S. citizen at the time of your birth, that parent must have resided in the United States for at least ten years, at least five of which had to be after the age of 16." Since Barack Obama only had one U.S. citizen parent (his mother), and his mother had not been residing in the U.S. for at least five years after the age of 16 when Barack was born (because she herself was only 18 at the time), then he's not a natural-born citizen.
A few facets of this claim immediately jump out as being far-fetched: first, that a sitting U.S. Senator who has already spent a good deal of time and money securing his party's nomination for the presidency would suddenly be discovered as ineligible due to an obscure provision of U.S. law; and second, that U.S. law would essentially penalize someone who would otherwise qualify for natural-born citizenship status simply because his mother was too young. The fact is, the qualifications listed in the example quoted above are moot because they refer to someone who was born outside the United States. Since Barack Obama was born in Hawaii, they do not apply to him.
The Fourteenth Amendment states that "all persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States." Since Hawaii is part of the United States, even if Barack Obama's parents were both non-U.S. citizens who hadn't even set foot in the country until just before he was born, he'd still qualify as a natural-born citizen.
The fact that people are claiming that having only one parent who is a US citizen does not qualify Obama as being a natural born citizen is especially ridiculous when presented alongside the fact that many of the same people were arguing changing the constitution to prevent the use of so called anchor babies not too long ago.