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Status as a natural-born citizen of the United States is one of the eligibility requirements established in the United States Constitution for election to the office of President or Vice President. This requirement was intended to protect the nation from foreign influence.
The Constitution does not define the phrase natural-born citizen, and various opinions have been offered over time regarding its precise meaning. A 2011 Congressional Research Service report stated that
The weight of legal and historical authority indicates that the term "natural born" citizen would mean a person who is entitled to U.S. citizenship "by birth" or "at birth", either by being born "in" the United States and under its jurisdiction, even those born to foreign parents; by being born abroad to U.S. citizen-parents; or by being born in other situations meeting legal requirements for U.S. citizenship "at birth". Such term, however, would not include a person who was not a U.S. citizen by birth or at birth, and who was thus born an "alien" required to go through the legal process of "naturalization" to become a U.S. citizen.[1]