In an earlier post, I suggested that perhaps intermarried Jews today have the status of tinokos she-nishbu, Jews who have been insufficiently educated in that matter. R. Mordechai Willig suggested something similar in his recent TorahWeb devar Torah (link):
We can try to apply these concepts to contemporary times. For example, today, most of those who condone, or even promote, intermarriage or homosexuality do not knowingly reject the Torah. They were never taught properly, and might theoretically be eligible for the Korban Pesach (see Rambam, Hilchos Mamrim 3:1-3). We should attempt to influence such individuals with words of peace until they return to the strength of Torah (ibid). The Rambam’s strategy of causing the elimination of reshaim, and the Hagada’s advice to ignore a rasha and thereby set his teeth on edge (Gra), no longer apply.Barukh she-kivanti le-da'ato ha-ramah.
According to the Chazon Ish (Yoreh Deah 2:16), strong-arm tactics have no place in our world. Employing such tactics against one who knowingly rejects Torah is counterproductive, and, therefore, prohibited when most Jews are not observant. Rather, we should attempt to bring them back to Torah with love. This kiruv imperative, however, makes the danger of our being influenced by anti-Torah beliefs and practices more potent and insidious. The need to strengthen our faith and commitment, as well as our children’s, is greater than ever.