Barack has one "r". Just thought I'd throw that out there. Hope you find your answer, but I do not know of American Citizens who have become President of another country. I do know of a few that were - for lack of a better term - trained in America. For example, Gonzalo Sanchez de Lozada or "Goni" in Bolivia who won on the back of American political backers.

Hopefully, you find a better answer to your questions.