in which he instructs to fulfill commandments with non-Jews, not only "because of peaceful ways"
The laws of foreign worship no longer apply to the non-Jewish nations. Therefore, even were "Israel to have a mighty hand" we would not be obliged, in any sense whatsoever, to treat the nations of our day according to the laws applying to idolatry. In all that concerns the relations between Jews and non-Jews, both in Israel and abroad, this means that these relations are not to be maintained only "because of peaceful ways", but because by Halachic definition they no longer engage in foreign worship. Therefore, ensuring their livelihood, visiting their sick, burying their dead, and comforting the mourners among them are all to be done out of moral obligation.
'Aseh Lecha Rav, Part 9, question 30, p. 73, The Committee for the Publication of HaGaon Rav Haim David Halevy, Tel Aviv, 1986