“Scripture is referring to an optional war”
Rashi, following the Sages (Kiddushin 21b and Midrash Tanhuma), explains the juxtaposition of the passages of “the beautiful [captive] woman,” the “hated woman,” and the “rebellious son.” He writes:
[and you desire her,] you may take [her] for yourself as a wife [Not that you are commanded to take this woman as a wife,] but the Torah [in permitting this marriage] is speaking only against the evil inclination [, which drives him to desire her]. For if the Holy One, blessed is He, would not permit her to him, he would take her illicitly. [The Torah teaches us, however, that] if he marries her, he will ultimately come to despise her, as it says after this, “If a man has [two wives-one beloved and the other despised]” (verse 15); [moreover] he will ultimately father through her a wayward and rebellious son (see verse 18). For this reason, these passages are juxtaposed. — [Tanhuma 1]
(Rashi Devarim 21:11, Judaica Press translation)
I think that the key phrase here is “the Torah is speaking only against the evil inclination.” The Holy One blessed be He knows man’s soul and inclinations, and so He is willing not to have the Torah “prohibit” something that many people are likely in any case to do in time of war. However, the juxtaposition of passages seems to teach us that all which follows (hate of the captive woman and the birth of the criminal son) result directly from the surrender to libidinous behavior that takes no account of any moral value. After all, Rashi, following the Sages, interprets beautiful woman as “even a married woman.” Scripture does not explicitly tell us how what the beautiful woman’s own position is towards all of this, how she feels about the enemy soldier who “took” her. However, since the Torah goes on to tell us that she shall stay in your house, and weep for her father and her mother for a full month, we may assume that this might even be a case of rape. The Torah also commands that if the man who took her in the storm of battle grows tired of her, he must release her and receive no compensation for his “loss” - You shall not keep her as a servant, because you have afflicted her. It is an affliction for a woman to be taken on the field of battle.
I think that the range of examples covered by Rashi’s explanation of the juxtaposition of passages (as suggested by the Sages) can be extended on the basis of something Rashi writes in the beginning of the parasha, again following the Sages in Sifrei:
If you go out to war The verse here is referring to an optional war.
The word if [Hebrew: ki] indicates a situation that is dependent upon human decisions. This is not an obligatory war, but rather one initiated by the nation’s leadership.
RaMBaM offers concise definitions of obligatory and optional wars:
At first the king may only fight obligatory wars. Which wars are obligatory? The war against the Seven Nations, the war against Amalek, and the defense of
Israel against an enemy that has come upon them. Afterwards he may fight optional wars; these
are the wars he fights against other nations in order to expand Israel’s
borders and to increase his greatness and fame.
(Hilkhot Melakhim 5:1)
The literal war against Amalek (rather than the eternal and symbolic war against absolute evil) and the war against the Seven Nations are merely of historical interest (“their memory is lost”). The only war that can be called an “obligatory war” today is one fought in “the defense of Israel against an enemy that has come upon them,” i.e., a unavoidable war intended to protect the nation from attack by an enemy that threatens its existence. All other wars are “optional wars.”
A halakhah found in Mishnah Sanhedrin 1:5 states:
An optional war is only waged with the permission of the Court of Seventy-One [judges].
That is to say: the highest judicial authority must oversee the political leadership’s decision to fight an “optional war,” and they must not be dragged into such a war by emotionalism and impulsivity.
The very term reshut - “optional” may require study and clarification. Certainly the Torah does not relate positively to the taking of the “beautiful woman,” and the explication cited by Rashi makes this unambiguous. The word “optional” often refers to situations that are not prohibited by the Torah but which are also not viewed as positive or desirable by the Torah.
The Mishnah and Gemara in tractate Makkot (chapter 2) deal with the case of a blood avenger who “murdered” an accidental killer who had left the city of refuge. The halakhah adopts R. Akiva’s view, which states: the blood avenger has reshut [the option of killing the accidental killer]. In his Commentary on the Mishnah and in the Mishneh Torah, RaMBaM explains that this refers to a situation in which the accidental killer deliberately left the city of refuge. The Torah uses the term murdered [ratzah]: and the blood-avenger murdered the murderer. True, the avenger will not stand trial for this murder, but his act is still referred to as a murder.
Along these lines, HaRAYaH Kook ztz”l sees a kind of “hidden rebuke” in the Torah’s formulation regarding the eating of meat: for it is your soul’s desire to eat meat.
A similar idea is expressed by R. Yohanan’s famous dictum regarding the reason for
R. Yohanan said:
Jerusalem was destroyed
only because they judged there according to the laws of the Torah. Should they then have ruled
arbitrarily?! Rather say: They based
their judgments upon the laws of the Torah and did not go beyond the letter of
(Bava Metzia 30b)
The blanket command, and you shall do the right and the good, does not relate to specific halakhic categories. I think that all the examples brought have something clear to say about the spiritual and moral plane of meta-halakhah, which stands beyond the concepts “permitted” and “prohibited.” The category of reshut is not identical with the desirable and the moral, the straight and good in the eyes of God and man. Rather, it refers to a certain region of human and social behaviors that are not prohibited by the Torah in a formal, halakhic, sense.
The Torah may be trying to relay to us an important message through the existence of the zone of reshut. The Torah restricts human behavior with formal and external limits; the “four cubits o the halakhah” represent a legal-social framework that makes the minimal demands required of a Jew. However, these demands do not command the good and the straight, the worthy, the moral, and the spiritually exalted.
Everything connected to this realm of “beyond the letter o the law” and “saintly virtue” is given over to the prerogative of human individuals and societies
I think that we can extend the message arising from Rashi and the Sages’ explication of the juxtaposition of passages in terms of “the Torah is speaking only against the evil inclination” to the very beginning of our parasha.
The national leadership is apt to mobilize the people for an “optional war” in order, as the RaMBaM says, “to expand
borders and to increase his greatness and fame.” The motivation for war may be politico-territorial
or connected to considerations of personal prestige. If such a decision is not ratified by an
independent judicial authority (the Sanhedrin of Seventy-One) there is a great
danger of wars motivated by the universal human drive for conquest.
The Torah spells out for us what may happen when people choose to wage a war which, while not “prohibited” – in as much as “the Torah is speaking only against the evil inclination.” That scenario teaches us that every individual, every society, every nation and every state is granted the freedom to choose between surrender to the drive for conquest and moral behavior requiring self-control and moderation.
The Torah also teaches us that each choice made by an individual or a society influences their respective characters. “Our Father Who is in Heaven, bless the State of
Your light and truth to its leaders, ministers, and advisors, and help them
with Your good counsel.”