(4) And He shall judge between the nations, And shall decide for many peoples; And they shall beat their swords into plowshares, And their spears into pruninghooks; Nation shall not lift up sword against nation, Neither shall they learn war any more.
1 and 2 are among the sources from the Later Prophets with a more peaceful message, implying that the ideal goal is that there will be no more war in the world.
David Hamelech is told that he was not allowed to build the Beit Hamikdash as a divine punishment for being a warrior. Hardly an endorsement of the culture of war.
(י) כִּֽי־תִקְרַ֣ב אֶל־עִ֔יר לְהִלָּחֵ֖ם עָלֶ֑יהָ וְקָרָ֥אתָ אֵלֶ֖יהָ לְשָׁלֽוֹם׃ (יא) וְהָיָה֙ אִם־שָׁל֣וֹם תַּֽעַנְךָ֔ וּפָתְחָ֖ה לָ֑ךְ וְהָיָ֞ה כָּל־הָעָ֣ם הַנִּמְצָא־בָ֗הּ יִהְי֥וּ לְךָ֛ לָמַ֖ס וַעֲבָדֽוּךָ׃ (יב) וְאִם־לֹ֤א תַשְׁלִים֙ עִמָּ֔ךְ וְעָשְׂתָ֥ה עִמְּךָ֖ מִלְחָמָ֑ה וְצַרְתָּ֖ עָלֶֽיהָּ׃ (יג) וּנְתָנָ֛הּ יְהוָ֥ה אֱלֹהֶ֖יךָ בְּיָדֶ֑ךָ וְהִכִּיתָ֥ אֶת־כָּל־זְכוּרָ֖הּ לְפִי־חָֽרֶב׃ (יד) רַ֣ק הַ֠נָּשִׁים וְהַטַּ֨ף וְהַבְּהֵמָ֜ה וְכֹל֩ אֲשֶׁ֨ר יִהְיֶ֥ה בָעִ֛יר כָּל־שְׁלָלָ֖הּ תָּבֹ֣ז לָ֑ךְ וְאָֽכַלְתָּ֙ אֶת־שְׁלַ֣ל אֹיְבֶ֔יךָ אֲשֶׁ֥ר נָתַ֛ן יְהוָ֥ה אֱלֹהֶ֖יךָ לָֽךְ׃ (טו) כֵּ֤ן תַּעֲשֶׂה֙ לְכָל־הֶ֣עָרִ֔ים הָרְחֹקֹ֥ת מִמְּךָ֖ מְאֹ֑ד אֲשֶׁ֛ר לֹא־מֵעָרֵ֥י הַגּֽוֹיִם־הָאֵ֖לֶּה הֵֽנָּה׃ (טז) רַ֗ק מֵעָרֵ֤י הָֽעַמִּים֙ הָאֵ֔לֶּה אֲשֶׁר֙ יְהוָ֣ה אֱלֹהֶ֔יךָ נֹתֵ֥ן לְךָ֖ נַחֲלָ֑ה לֹ֥א תְחַיֶּ֖ה כָּל־נְשָׁמָֽה׃ (יז) כִּֽי־הַחֲרֵ֣ם תַּחֲרִימֵ֗ם הַחִתִּ֤י וְהָאֱמֹרִי֙ הַכְּנַעֲנִ֣י וְהַפְּרִזִּ֔י הַחִוִּ֖י וְהַיְבוּסִ֑י כַּאֲשֶׁ֥ר צִוְּךָ֖ יְהוָ֥ה אֱלֹהֶֽיךָ׃
(10) When thou drawest nigh unto a city to fight against it, then proclaim peace unto it. (11) And it shall be, if it make thee answer of peace, and open unto thee, then it shall be, that all the people that are found therein shall become tributary unto thee, and shall serve thee. (12) And if it will make no peace with thee, but will make war against thee, then thou shalt besiege it. (13) And when the LORD thy God delivereth it into thy hand, thou shalt smite every male thereof with the edge of the sword; (14) but the women, and the little ones, and the cattle, and all that is in the city, even all the spoil thereof, shalt thou take for a prey unto thyself; and thou shalt eat the spoil of thine enemies, which the LORD thy God hath given thee. (15) Thus shalt thou do unto all the cities which are very far off from thee, which are not of the cities of these nations. (16) Howbeit of the cities of these peoples, that the LORD thy God giveth thee for an inheritance, thou shalt save alive nothing that breatheth, (17) but thou shalt utterly destroy them: the Hittite, and the Amorite, the Canaanite, and the Perizzite, the Hivite, and the Jebusite; as the LORD thy God hath commanded thee;
Although there is some ambiguity as to the differences between the cities in Israel and those that are "far away" (discussed in sources 6-9) it is clear that if you are unable or not allowed to make peace you must then kill either all the men or sometimes even the women and children.
The reason given (and further expounded by the Chinuch in source 12) is that we don't want to learn from and imitate the idol worshiping ways of these people.
רש"י דברים פרשת שופטים פרק כ
(י) כי תקרב אל עיר - במלחמת הרשות הכתוב מדבר, כמו שמפורש בענין (פסוק טו) כן תעשה לכל הערים הרחוקות וגו':
When you come close to the city- The verse refers to an optional war, as is explicitly stated later (in verse 15) "so shall you do to all the cities which are distant..."
Rashi is explaining that only by an Optional War (i.e. Milhemet Reshut) do we offer peace. This is in contrast to the Obligatory War (i.e. Milchemet Mitzvah) of verse 15 where we are commanded to destroy every living thing (seemingly without first making a peace overture)
רשב"ם דברים פרשת שופטים פרק כ
(טז) לא תחיה כל נשמה - כשתבא להלחם עליהם לא תקרא להם לשלום, כמו שפרשתי לך בשאר אומות, אבל אם יבאו אליך מדעתם להיות עבדיך קודם שתלך עליהם כמו הגבעונים יכול אתה להחיותם:
Do not allow any soul to live- When you come to fight a war do not "call out" in peace, as with the other nations. However if they come to you to serve you (i.e. live as Geiri Toshav) before you come to them, like with the Gibeonites, you are allowed to let them live.
Rashbam (in contrast to Rashi) would allow you to accept a peace offer initiated by one of the Seven Cannanite Nations prior to a Milhemet Mitzvah, just not offer one to them.
רמב"ן דברים פרשת שופטים פרק כ
(י) כי תקרב אל עיר להלחם עליה וגו' -
במלחמת הרשות הכתוב מדבר, כמו שמפורש בענין (פסוק טו), ... אבל קריאת השלום אפילו במלחמת מצוה היא, שחייבים לקרא לשלום אפילו לשבעה עממים, שהרי משה קרא לשלום לסיחון מלך האמורי, ולא היה עובר על עשה ועל לא תעשה שבפרשה, כי החרם תחרימם (פסוק יז) ולא תחיה כל נשמה (פסוק טז). אבל הפרש שביניהם כאשר לא תשלים ועשתה מלחמה, שצוה הכתוב ברחוקות להכות את כל זכורה ולהחיות להם הנשים והטף בזכרים, ובערי העמים האלה צוה להחרים גם הנשים והטף:
The verse is speaking about an optional war as is explicit later (in verse 15 when it identifies them as "distant cities")... But you should make peace overtures even with the seven nations , just like Moshe made peace overtures to Sihon King of the Amori. In this way you are not violating both a positive and a negative commandment from this section "but thou shalt utterly destroy them" (verse 17)and "thou shalt save alive nothing that breatheth." The difference (obligatory and optional wars), is that when you do not make peace and wage war ; with those "far away" you should kill the men but allow the women and children to live, whereas by these cities (in Israel) you must utterly destroy even the women and children.
The Ramban says that in both optional and obligatory wars we must make peace overtures. The only difference between the two he says , is that in an optional war you kill only the men whereas by the obligatory war (i.e. with the 7 nations) you must kill the men, women, and children.
רמב"ם הלכות מלכים פרק ו הלכה א
אין עושין מלחמה עם אדם בעולם עד שקוראין לו שלום אחד מלחמת הרשות ואחד מלחמת מצוה,
You may not wage war on ANYONE in the world until you make peace overtures, whether it is an optional or obligatory war.
These Pesukim seem to back up the Ramban and Ramban in implying that peace overtures were made to all the nations in Israel.
The fact that the Joshua made peace with the Gibeonites (even though they used subterfuge) shows that Joshua was willing to make peace with the Cannanite natives.
(2) and ye shall make no covenant with the inhabitants of this land; ye shall break down their altars; but ye have not hearkened unto My voice; what is this ye have done? (3) Wherefore I also said: I will not drive them out from before you; but they shall be unto you as snares, and their gods shall be a trap unto you.’
Here we are chastised by the Navi for violating God's word by making a covenant with the Cannanite nations (and not destroying them). The natural consequence is that we will inevitably learn from the idol worshiping ways of the natives. In fact the entire Sefer Shoftim is the story of the Bnei Yisrael repeatedly being ensnared by the idols of the natives.
ספר החינוך מצוה תכה
מצות הריגת שבעה עממין
לפי שאלו השבעה עממים הם שהחלו לעשות כל מיני עבודה זרה וכל תועבות ה' אשר שנא, ועל כן בהיותם עיקר עבודה זרה ויסודה הראשון נצטוינו עליהם למחותם ולאבדם מתחת השמים, לא יזכרו ולא יפקדו בארץ החיים. ובמצותנו זאת עליהם להחרימם ימצא לנו תועלת, שנאבד זכרם מן העולם ולא נלמוד ממעשיהן. וגם יש לנו ליקח מוסר בזה שלא נפנה אחר עבודה זרה
Since it is these seven nations who practice idolatry and all manner of abominations to God that are hated. Therefore, since their essence and essential foundation is idolatry we are commanded to utterly destroy them from under the heavens, that they should not be remembered or counted in the land of the living. The benefit to be found for us in this commandment to utterly destroy them and forget their name from the world, is that we will not learn from their actions. We can also learn a moral lesson not to turn towards idol worship.
The Chinuch posits the fact that they are not only idolaters but also involved in unnamed abominations makes them "hated" by God. Additionally, the Mitzvah is meant to keep us from learning from their actions and imitating them.
(14) And the LORD said unto Moses: ‘Write this for a memorial in the book, and rehearse it in the ears of Joshua: for I will utterly blot out the remembrance of Amalek from under heaven.’
In possible contrast to the seven nations the mitzvah of destroying Amalek is eternal.
(יז) זָכ֕וֹר אֵ֛ת אֲשֶׁר־עָשָׂ֥ה לְךָ֖ עֲמָלֵ֑ק בַּדֶּ֖רֶךְ בְּצֵאתְכֶ֥ם מִמִּצְרָֽיִם׃ (יח) אֲשֶׁ֨ר קָֽרְךָ֜ בַּדֶּ֗רֶךְ וַיְזַנֵּ֤ב בְּךָ֙ כָּל־הַנֶּחֱשָׁלִ֣ים אַֽחַרֶ֔יךָ וְאַתָּ֖ה עָיֵ֣ף וְיָגֵ֑עַ וְלֹ֥א יָרֵ֖א אֱלֹהִֽים׃ (יט) וְהָיָ֡ה בְּהָנִ֣יחַ יְהוָ֣ה אֱלֹהֶ֣יךָ ׀ לְ֠ךָ מִכָּל־אֹ֨יְבֶ֜יךָ מִסָּבִ֗יב בָּאָ֙רֶץ֙ אֲשֶׁ֣ר יְהוָֽה־אֱ֠לֹהֶיךָ נֹתֵ֨ן לְךָ֤ נַחֲלָה֙ לְרִשְׁתָּ֔הּ תִּמְחֶה֙ אֶת־זֵ֣כֶר עֲמָלֵ֔ק מִתַּ֖חַת הַשָּׁמָ֑יִם לֹ֖א תִּשְׁכָּֽח׃ (פ)
(17) Remember what Amalek did unto thee by the way as ye came forth out of Egypt; (18) how he met thee by the way, and smote the hindmost of thee, all that were enfeebled in thy rear, when thou wast faint and weary; and he feared not God. (19) Therefore it shall be, when the LORD thy God hath given thee rest from all thine enemies round about, in the land which the LORD thy God giveth thee for an inheritance to possess it, that thou shalt blot out the remembrance of Amalek from under heaven; thou shalt not forget.
Amalek attacked a weak opponent with no defenses. His need to destroy us even at risk to himself
רש"י דברים פרשת כי תצא פרק כה
אשר קרך בדרך: ...דבר אחר לשון קור וחום, צננך והפשירך מרתיחתך, שהיו כל האומות יראים להלחם בכם ובא זה והתחיל והראה מקום לאחרים. משל לאמבטי רותחת שאין כל בריה יכולה לירד בתוכה, בא בן בליעל אחד קפץ וירד לתוכה. אף על פי שנכוה,הקרה אותה בפני אחרים:
... Another explanation its a language of cold and hot. (as in) He cooled you off and made you warm when you were boiling hot. This is because all the nations were scared to go to war with them and then they came and showed everyone else how to fight with (i.e. that its possible). It's like a parable to a boiling hot bath than nobody is able to submerge in. Along comes an irresponsible man and jumps in. Even though he gets burned, he cools off the water for everyone else.
Rashi (quoting a Medrash) explains that Amalek attacked us despite knowing that they would only harm themselves in the process. They did it to encourage others to try to harm us. This shows that they are fundamentally dedicated to our destruction.
ספר החינוך מצוה תרד
מצוה להכרית זרעו של עמלק
שנצטוינו למחות זרעו של עמלק ולאבד זכרו מן העולם זכר ונקבה גדול וקטן...
ובאמת כי גם על כל יחיד מישראל הזכרים מוטל החיוב להרגם ולאבדם מן העולם אם יש כח בידם בכל מקום ובכל זמן אם אולי ימצא אחד מכל זרעם.
We are commanded to utterly destroy the seed of Amalek and to blot out their memory from the world man, women, adult, and child. ... In truth this is also (incumbent) on each and every individual Male Jew; that there is and obligation on him to kill and blot out from the world, if he has the ability, in every place and in every time if he finds even one person from this lineage.
It is generally understood that we can no longer identify Amalek. However if we were able to identify them the Chinuch (as well as almost all other Meforshim) believe that the Mitzvah would continue to be incumbent nationally as well as individually.
Being Frum and Being Good:
On the Relationship Between Religion and Morality
Rabbi Aharon Lichtenstein
“Wiping out Amalek does not conform to what we would normally expect a person to do. Normally, you should not be killing ‘from child to suckling babe.’ But I’m not saying, God forbid, that it is immoral in our case, where God has specifically commanded the destruction of Amalek—‘A faithful God, without iniquity, righteous and upright is He’ (Devarim 32:4). Although generally such an act would be considered immoral, it assumes a different character when God, from His perception and perspective, commands it. The same holds true of the akeida—it demanded that Avraham do something which normally is immoral. But in the context of the divine command, surely it partakes of the goodness and morality of God. We must admit, though, that there is a conflict in this case between the usual moral norm and the immediate tzav given here.”
Questions contemplate further:
1. Is our war of Kivush Eretz Yisrael fundamentally different than the Crusades and Jihad?
2. Is the relative merit of the three religious wars dependent on which religion one believes is true?
3. Can we judge the "morality" of an action outside of whether we believe it is a divine commandment? If God had not commanded these religious wars would we consider them to be immoral?
4. Is the Biblical commandment of genocide contradicted other sources? If so how do we understand these contradictory messages?
5. Why are we sometimes commanded to kill the men (i.e. the fighters) and sometimes the women and children as well?
6. Are the reasons given for the Mitzvah of "Killing the Seven Nations" or "Blotting Out Amalek" any different than the reasons given for the Crusades and Jihad?
7. In what ways is Amalek considered to be worse than even the Seven Nations? Does this convince you that the Mitzvah of "Blotting out Amalek" is without moral quandary?
8. As the Jews are repeatedly criticized by the Prophets for not completing the genocide (and their subsequent moral failings due to this), is it fair to focus on this as a positive expression of the Jews Midah of Mercy?
9. Do you believe that if you encountered someone who was a descendant of Amalek that you could fulfill the commandment? Would it matter if this person was a women, child, or a friend?