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Cosgrove: Jewish law can guide Israel to fight a just war

“The question is not whether Israel has the right to defend itself, but whether Israel will be smart and moral in this war of obligation.”

War is horrible —  and, sometimes, a necessity. Is there a way Israel’s aims can be both achieved and understood by the world as justified?

Philosophical discussions of “just war theory” historically are broken into two categories: Questions about the initiation of war — jus ad bellum, in Latin — and about the conduct of war, jus in bello.

Israel, of course, did not initiate this war. It began when Hamas savagely attacked Israel at dawn on Oct. 7, murdering some 1,400 Israelis, wounding thousands and taking more than 200 men, women, seniors, children and babies hostage.  

The first obligation of any state or sovereign authority is to ensure the safety and security of its citizens. This obligation is altogether consistent with Jewish law. Building on the right of a homeowner to self-defense outlined in Exodus, the Talmud teaches: “If someone comes to kill you, rise up to kill him first.”  

It was the great 12th century codifier of Jewish law, Moses Maimonides, who gave fullest expression to the different categories or kinds of war. Wars of choice – in Hebrew, milhemot reshut — and wars of obligation, milhemot hovah

Wars of choice include efforts to enlarge a nation’s territory or prestige. Wars of obligation are those  conducted in self-defense — in Maimonides’ words, “to deliver Israel from an enemy who has attacked them,” or “so Israel’s enemies will not march against them.”

Judaism is not a pacifist religion. We do not stand idly when our brother’s blood has been shed, nor when the life of our kin is at risk. 

Our Torah outlines the laws of rodef – the obligation to intervene to stop a pursuer from killing another person. It is an obligation that takes on an increased urgency when civilians are held hostage. There is a specific, additional mitzvah of pidyon shvuyim, working to release captives, as seen in the book of Genesis when Abraham goes to war to rescue his family — and in 1976 when Israel rescued the hostages in Entebbe. 

There is no doubt, then, that in this moment Israel has not only the right but the obligation to defend itself and to redeem the hostages, to ensure that the horrors of Oct. 7 never happen again. To suggest otherwise is to hold the state of the Jews to a standard different than any other nation.

Jewish law also offers guidance regarding the second category, the ethics of conduct within war. Maimonides teaches that when besieging a city, fighters may surround on three sides but not four – presumably so refugees can flee for their lives. Remember that Egypt, not Israel, controls the Rafah crossing in Gaza’s south.

When our patriarch Jacob was anticipating battle with his brother, Esau, Jacob was both “afraid and distressed.” The Maharal of Prague, a 16th century rabbinic scholar, asks why the Torah employs two adjectives when one should have been enough. He posits that Jacob was afraid for his own safety — and distressed at the thought that the battle might force him to take the life of another.  

Enemy lives are not worth more or less than Jewish lives – we are all created equally in the image of God. As Jews, we dare not let the inhumane actions inflicted on us prompt us to lose our own humanity.  

In practical terms, all this leaves Israel with a series of difficult choices. The question is not whether Israel has the right to defend itself, but whether Israel will be smart and moral in this war of obligation.  

Israel must perform the near-impossible balancing act of self-defense, securing its borders, limiting the death of its own soldiers and innocent civilians, redeeming the hostages and pursuing peace. 

Will Israel make sure the medicine does not cause more harm than the illness? The best we can hope is that the Jewish state will prosecute this war as it has prosecuted others, and make the best imperfect decisions based on the information it has, knowing that even those decisions will come with a heavy cost

In Hamas, Israel is fighting an enemy that does not follow any laws of warfare. Far too many fail to understand that Hamas neither represents nor serves the interests of the Palestinian people.  

In co-mingling with civilian populations, in stealing humanitarian aid, in placing military assets under hospitals and beneath schools, in cutting off access to escape or relief – Hamas itself is responsible for the deaths of thousands of Palestinian civilians in this war and those that came before.  

The brutality of Hamas is being overlooked while Israel is being held to a different standard than any other nation, whether because of ignorance or something more nefarious. It is a difference that betrays antisemitism, and — uncomfortable as this may be — it is also clarifying and should make our resolve more firm.

The decisions of the coming days, weeks and maybe months will be tortured. Sometimes Israel will get it right, and sometimes Israel will get it wrong. The fact that Israel, unlike the other side, is asking questions of just war is what makes Israel worth defending.

Thank God the Jewish people have a sovereign state and army, are able to fight this war and debate how to do so justly. Given the choice of Israel’s difficult decisions or the moral purity of exiled victimhood, we should choose the former. It is the foundation of what this war is all about:  the right of Jews to self-determination.  

Elliot Cosgrove is the rabbi of Park Avenue Synagogue in Manhattan.

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