In Hilchot Melachim U’Milchamot, the Rambam brings down that neither convert (nor their direct descendants) nor women can serve in any official position of authority in Eretz Yisrael; he brings the examples of a Nasi, a Dayan, and an army commander. As the child of a convert (my mother) myself, I was wondering the practical application of these Halachot in the modern Medinah. Should I not accept an offer to become a commander should I join the IDF? In general, is it permissable for women of converts to serve as mayors, judges, or MK’s in Israel?
There is more than one approach to this matter. According to the lenient opinion, if the people accept them as an authority it is Halachacly acceptable, (like in the case of Shemaya and Avtalion). Especially in the case of a convert one should follow the lenient approach to accommodate the Mitzvah of loving the Ger. Even according to the more strict approach, if you are offered a position it is not your Halachic duty to reject it since it is not a Mitzvah on you rather on the community. (Igrot Moshe YD 4 26; Tzitz Eliezer 19 47)