Ramifications of dual citizen using his non-US passport to enter America

[AK84]

The comment you were remembering was something which happened to my old workmate.

@AK84

Or Accidental Americans like my old workmate. He was born in DC to a world bank worker and went back to Israel when he was 1. Next time he went to the US was on a work meeting and we found out that he had been turned back because his passport said born in the US.

Though if I recall correctly, he was using a UK passport (Mum was British) when he was turned back.
In the years since the episode (2009 or so) he has moved to LA after falling in love with an American doctor, so presumably he does have a US passport now.