Mankind is required to keep the 7 Noahide Laws. These laws include:
1) Do not murder.
2) Do not steal.
3) Do not worship false gods.
4) Do not be sexually immoral.
5) Do not eat a limb removed from a live animal.
6) Do not curse God.
7) Set up courts and bring offenders to justice.
These are all capital offenses!
Jews are required to keep 613 commandments (I'm not going to list them here). The ten commandments are included in the 613.
One must understand that we have two different sets of laws for two different groups: If a Jews eats pork chops, the penalty is 39 lashes. A gentile is allowed to eat pork chops, and lots of other things that are forbidden to Jews. A Jew that lights a fire on the Sabbath has committed a capital offense. There is no such prohibition for gentiles.
So if the authors of Torat HaMelech write that "Thou shalt not murder" does not apply to non-Jews, they are correct. Indeed from an objective reading of Exodus chapters 19 and 20 it is clear that the ten commandments were given to the Jewish People.
Does this mean that the Torah permits Jews to murder gentiles? The authors of Torat Melech make it clear, over and over again, that the Torah forbids murdering gentiles. This is learned from the rule that "There is nothing that is forbidden for gentiles that is permitted for Jews"(Sanhedrin 59A).
However, when a war is being waged the rules are different. FDR, Harry Truman, and LBJ would all clearly understand this.
Of course, all this does not prevent the distorters from distorting.
I can only endorse what Rabbi Yoel Schwartz and Rabbi Yeshayahu haCohen Hollander said regarding them:
If not for the newspaper Haaretz, which published a story on the book, the religious community probably would not have heard of it. The newspaper published its contents in a partial and perverted manner, as part of its tendency of the newspaper and its owners and members of its system to slander the rabbis of the settlements, residents of the settlements, all of mitzvah observant Judaism, and all the principles of Judaism. They are prepared, as part of their war on the religion of Israel, to slander, by means of partial quotes, their Jewish brethren, in spite of them knowing, as journalists, that they were quoted amidst further falsification, and in a manner which causes anti-Semitism, and hatred of Israel, and even though they are endangering the peace of all the Jews in the Diaspora.