[Behind the Blue Wall]

If you think that foreign women who marry American men automatically become U.S citizens without having to be naturalized, you’re even further behind the eight-ball here than I might’ve thought. I married a foreign woman who NATURALIZED as an American citizen several years later.

Congress was explicitly granted the power in the Constitution to determine the rules for immigration and naturalization. No such power was granted to determine natural born citizenship.

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If you think that foreign women who marry American men automatically become U.S citizens without having to be naturalized, you're even further behind the eight-ball here than I might've thought. I married a foreign woman who NATURALIZED as an American citizen several years later.

I said "for a long time" That was the law from 1855 to 1922. Wilson's mother became a US citizen when she married his father without having to officially renounce her loyalty to Britain. Ditto with Hoover's Canadian-born mother.

Congress was explicitly granted the power in the Constitution to determine the rules for immigration and naturalization. No such power was granted to determine natural born citizenship.

But changes in the law of naturalization meant changes in the natural born citizenship status of individuals (if you accept the idea that "natural born citizens" are different from other citizens from birth).