Mourning for a secular Israeli

Q: Does one sit shiva for a secular Israeli?
A: It is true that we do not sit shiva for one who separates himself from the ways of the community (Rambam, Hilchot Avel 1:10 and Shulchan Aruch, Yoreh Deah 345:5). The Rambam says (ibid.) that people who separate themselves from the community are "The people who cast off the yoke of the mitzvot from their necks and are not included among the community of Israel." And the Shulchan Aruch writes (ibid.): "They are like free people for themselves like the rest of the nations." This means that they are people who left the Nation of Israel and someone who leaves defines himself as an outsider. But Maran Ha-Rav Kook makes an important clarification in his article "Al Bamotenu Chalalim" (Ma'amrei Ha-Re'eiyah, p. 89). He discusses the exact same question about shiva for two members of the secular movement "Ha-Shomer" who were killed in the Galil. Maran Ha-Rav Kook said that secular Jews are not defined as those who separate from the ways of the community. The separation which appears in the Rambam and the Shulchan Aruch is comprised of two parts: separation from Judaism and separation from the Nation of Israel. In the past, one went with the other, if one left the religion he left the Nation and he was outside. Maran Ha-Rav Kook says that today this is not so. Some people leave the religion but do not leave their connection to the Nation of Israel, and they display self-sacrifice for the Nation and are killed for the Nation as the members of the "Ha-Shomer" movement. Therefore, this law does not apply to them. As is known, in the language of Halachah, they are "Tinokot She-nishbu" (literally Jewish children captured and raise among non-Jews). The Rambam explains in Hilchot Mamrim (3:3) that a "tinok she-nishba" is a Jew who did not receive a proper Jewish upbringing and education. In simple words, they are confused. They do not separate themselves from the religion in order to destroy the Nation of Israel, they separate themselves because they do not know any better. The great authorities already ruled that these difficult halachot do not apply to secular Jews in our days, since they are "tinokot she-nishbu." This is also the opinion of the Chareidi authorities. For example, Nitei Gavriel (Hilchot Aveilut) quotes the Charedi authorities who rule that we do sit shiva for a "tinok she-nishba" - which is a secular Israeli today.