Copies of a new book that provides justification for the killing of non-Jews could not be found in Jerusalem at the beginning of the week. At Mercaz Harav Yeshiva, the flagship educational institution of Orthodox Zionism, there was a small sign in the entrance advertising the sale of Torat Hamelech: Dinei Nefashot Bein Yisrael Le'Amim (The King's Torah: Laws of Life and Death between Jews and the Nations) at a price of NIS 30. Those interested in buying the book were asked to place money in a small cup and take one. But the books were gone. Lior, a young man from Yitzhar, a settlement in Samaria, whose name and telephone number appeared on the advertisement for Torat Hamelech, was surprised at how quickly the books had been sold. "Really? They're all gone?" he said, adding that there was no other place in the Jerusalem area or anyplace else besides Yitzhar where the book could be found. Part of the reason for the interest was a front-page headline in Ma'ariv on Monday outlining the most shocking items from the book, such as halachic license to kill innocent children in battle situations in which their presence endangers Jewish lives, or even if there is concern that these young children will grow to become mortal enemies of Jews. The timing of the book's publication might also have something to do with the extensive media exposure it received. Distribution of the books came just over a week after it became known that Ya'acov Teitel, a settler from Shvut Rahel, had been arrested for allegedly murdering two Palestinians and severely wounding a Christian who belongs to a messianic Jewish community in Ariel. And even if the students at Mercaz Harav did not hear about the book from Ma'ariv, the subject of killing gentiles, and more specifically Palestinians as part of the ongoing battle against terrorism, is particularly relevant for students at the yeshiva who have served, are presently serving or plan on serving in the IDF. After all, a large portion of Torat Hamelech is dedicated to exploring Jewish "rules of engagement" according to the authors' interpretation of Jewish law. For many young men at Mercaz Harav or other Orthodox Zionist yeshivot where IDF service is combined with intense Torah learning, the book could have practical implications for how religious soldiers do battle. And at Mercaz Harav, it was just over a year ago that a Palestinian Muslim from east Jerusalem shot eight students dead. Another reason for the potential popularity of the book at Mercaz Harav is that its two authors have connections to the yeshiva. Rabbi Yitzhak Shapira, a student of the eclectic Chabad Rabbi Yitzhak Ginzberg and head of the Od Yosef Hai (Joseph Still Lives) Yeshiva, studied at Mercaz Harav's high school and spent time at the yeshiva as an older student. Rabbi Yosef Elitzur, the other author of the book, is the son of Rabbi Michael Hershkovitz, a teacher at Mercaz Harav. However, it could be that the sudden dearth of copies of Torat Hamelech is for another reason altogether. A librarian at Mercaz Harav said this week that the new book would not be included in the yeshiva's collection. Apparently, Rabbi Ya'acov Shapira, head of Mercaz Harav (no relation to Yitzhak Shapira), does not approve of the book. It is possible that Mercaz Harav's head ordered that the books not be sold in the yeshiva. True, the book has received the approbation of Kiryat Arba-Hebron Chief Rabbi Dov Lior, Rabbi Ya'acov Yosef, the son of Shas mentor Rabbi Ovadia Yosef, and Ginzberg. However, these rabbis do not represent the mainstream consensus of religious Zionism. One surprising exception is Rabbi Zalman Nechemia Goldberg, a highly respected halachic authority in both haredi and religious Zionist circles, who wrote an endorsement that appeared in the book. Copies were being distributed on Tuesday at the Yeshiva of the Jewish Idea in Jerusalem, which follows the philosophy of the late Rabbi Meir Kahane. The response of one leading religious Zionist media figure - which perhaps captures best the more right-wing elements within the religious Zionist mainstream - was dread. "I grabbed my head when I saw the headline in Ma'ariv," said the media source who went to school with one of the authors of the book. "I said to myself we have just managed to contain the media damage done to us by Teitel, by showing he is an isolated element, and now this happens. "I do not doubt the halachic conclusions of the book," added the source, "but the way they presented it was all wrong." According to the book, gentile noncombatants, including innocent children and babies, can be killed in situations in which their presence endangers, even indirectly, the lives of Jews. The book cites sources from the Bible, Talmud and later rabbinical literature to argue that the lives of non-Jews are worth less than those of Jews. Therefore, gentiles' lives can be forfeited if this reduces danger to Jewish lives. The book opens with the prohibition against killing gentiles. This prohibition is based primarily on the principle that Jews, out of a desire to protect themselves, should not incite non-Jews by killing them. The killing of non-Jews also causes a desecration of God's name. However, the 230-page book goes on to detail cases in which, according to the authors, Halacha permits killing non-Jews, for instance when they endanger, either directly or indirectly, the lives of Jews. In Halacha there is a term known as "rodef" which refers to an individual attempting to commit murder. In this case the Halacha permits a bystander to use force, even deadly force if necessary, to stop the potential murderer, whether he is Jewish or not. Shapira and Elitzur write that this holds true of a non-Jew "even when the person with the intent to murder is not doing so in a direct fashion but even in an indirect fashion. A civilian who helps combatants [fighting against Jews] is considered a rodef and it is permitted to kill him. "Anyone who supports the evil army in any way is a supporter of murderers and is considered a rodef. A civilian who encourages the war gives strength to the [enemy's] king and soldiers to continue the war. Therefore, every civilian in the sovereignty fighting against us that encourages the combatants or expresses his satisfaction with their actions is considered a person with an intent to kill. Therefore, he can be killed. And anyone who weakens our sovereignty with his or her speech is also considered a rodef." The authors of the book go on to say that it is permitted to kill minors as well, even if they are innocent, when they are situated in a place that blocks the saving of Jews' lives. Shapira and Elitzur refer to these minors as "blockers of rescue" "Little children are often situated in this way," they write. "They block the rescue of Jews and they do this against their will. Even so, it is permitted to kill them because their very presence facilitates the killing [of Jews]." The authors also advocate the killing of young children if it is foreseeable that these children will grow up to be enemies of the Jews. "There is an argument for killing the very young if it is clear that they will grow up to hurt us [Jews]. And in this situation the attack should be directed at them and not just indirectly while attacking adults," write Shapira and Elitzur. "It is also permitted to kill the children of the [evil] leader [of the enemy] in order to put pressure on him, if hurting the children will prevent the evil king from acting out his evilness." In a chapter titled "Attacking The Innocent" the two say that the main brunt of the war effort should be against those with an intent to kill but even someone who merely belongs to the nation of the enemy is considered an enemy. The authors also advocate revenge attacks. "Revenge is an essential [war] need to prove that evil behavior does not pay off." Therefore, "sometime one must commit ruthless acts that are designed to create the correct element of fear." Shapira and Elitzur also argue that individuals can make the decision to kill gentiles on their own. "One does not need a decision by the nation to permit the spilling of blood of those from the evil empire. Even individuals attacked by the evil sovereignty can retaliate."