Regarding the Nochri's obligation to learn and to fulfill the seven Mitzvos of Benei Noach and his liability if he does not do so, about which we responded in a previous discussion, there is a remarkable Chidush in "His'orerus ha'Teshuvah" of Rebbi Shimon Sofer (Budapest, published between 1923 and 1934; vol. 4, Yoreh De'ah #186). He writes as follows (translation):
"He is 'Karov l'Mezid,' considered to have sinned intentionally, since he should have learned and he did not learn, as the Rambam writes. In my humble opinion, this applies only when we are living in our land and we
have governing control, and all those who live among us are either Gerei Toshavim (who accepted upon themselves the seven Mitzvos of Benei Noach), or they are Nochrim whom we must put to death, as the Rambam writes
(Hilchos Melachim 8:10). Consequently, the Nochri who transgresses any of the seven Mitzvos should have learned from what he saw around him — all of the other Nochrim acting as Gerei Toshavim and observing the seven Mitzvos.
That Nochri certainly knows how the other Nochrim around him are conducting themselves as he hears and sees them himself, and thus he certainly should have learned from them.
However, now, when we are in exile, the Nochri [who transgresses the seven Mitzvos] has not heard nor has he seen nor does he know anything about the seven Mitzvos saw. Hence, from where should he have learned about the seven
Mitzvos and about his obligation to observe them, if he has never heard of them? Even though we are not permitted to cause him to transgress them because of 'Mipnei Iver,' nevertheless he is an absolute Shogeg. Proof to
this can be found in the Rambam who writes (in Hilchos Mamrim 3:3) that those Karaites who were raised by their fathers in a way of falsehood, even though they hear afterwards about the laws of the Jewish nation, they are considered as though they sin against their will (Anusim) and they have the status of 'a baby who was taken captive among the Nochrim….' Further proof to this can be found in the Ra'avad and Kesef Mishnah (in Hilchos Avodah Zarah 10:6).
With regard to forming free-loan societies for the Nochrim, it can be said that this is a Mitzvah and there is reward for doing so, and that these things should be done because of the Kidush Hashem involved and the recognition of the greatness of the faith of the Jews who do good for all. Indeed, the verse says, 'Hashem is good to all and His mercy is upon all of His creations' (Tehilim 145:9), and it says, 'Her (the Torah's) ways are ways of pleasantness, and her paths are of peace' (Mishlei 3:17)."
Source: http://www.mail-archive.com/daf-discuss@shemayisrael.com/msg00137.html
Other sources:
- The Obligation of Jews to Seek Observance of Noachide Laws by Gentiles: A Theoretical Review by Rabbi Michael J. Broyde
- Shiurium on the topic of "Non Jews " on YUTorah.org, in particular I recommend the series by Rabbi Hanan Balk on this topic