Professor Alderman to Rabbi Goldberg: The halachah is crystal clear. It is entirely legitimate to kill a rodef — that is to say, one who endangers the life of another — and this is true even if the rodef has not yet actually taken another life. So the Judaism that I practise permits what is generally referred to as “pre-emptive” military action. In this particular case, the ruling power, Hamas, has advertised (in its charter) that its mission is to kill Jewish people. Therefore every member and supporter of Hamas may be considered a rodef. What precise kind of pre-emptive military action might one take? A great deal has been said about “proportionality”. This may be a Christian idea, but thankfully it is certainly not a Jewish one.

Rabbi Goldberg to Professor Alderman: I have no argument with your explanation about the status of the rodef in Jewish law and the permissibility of taking pre-emptive action against him, except to add that the biblical law should be viewed in the context of a desert society and blood feuds between individuals and clans. That is why I disagree with your contention that in the context of modern Gaza this can be extended to include every member and supporter of Hamas — about 500,000 people according to the election results. Or would you advise every innocent civilian and child to wear a large placard visible to Israeli jets proclaiming “Don’t blame me, I voted for Fatah”? I am surprised at your dismissiveness of the Christian idea of proportionality. The “just war” doctrine, in which proportionality plays a major part, strikes me as a laudable attempt by medieval Christian theologians to try and control the worst excesses of war. There was no Jewish equivalent only because Jews had possessed neither country nor army since 135 CE, so the moral issues were academic. Even so, I would argue that proportionality is indeed a Jewish idea, going right back to the biblical legislation about “an eye for an eye”. As we know, it was always interpreted by Jewish law to mean monetary compensation to the value of the damaged eye, tooth, limb, etc — very precise proportionality indeed.

 Professor Alderman to Rabbi Goldberg: I suspect that you fail to appreciate the full meaning of rodef in this context. As you know, the source for this is the Babylonian Talmud, Sanhedrin 73a. It seems clear to me from a commonsense reading of this passage that the concept of a rodef encompasses those who advocate or incite the murder of Jews. Every Gazan citizen who voted for Hamas must — surely — come within this category, because Hamas as a movement is explicitly committed to the destruction, not simply of Israel, but of the Jewish people. The deaths of “innocents” is no doubt very regrettable. If Hamas really cared about this situation, it would capitulate. But, unfortunately, it shows no signs of doing so. Indeed, it regards the deaths of “innocents” in this conflict as a prize in itself, because (according to its perverse logic) in this way even children and old people can play their part in the global jihad that Hamas craves. As Hamas spokesman Fathi Hamad said on Al-Aqsa TV last year, what has been created is “a human shield of women, children, the elderly and the Jihad fighters against the Zionist bombing machine … we desire death as you desire life.” (Of course using human shields is itself a war crime, but, curiously, nobody seems much bothered on that account.) I have to say that you reference to the lex talionis [eye for an eye] seems to me irrelevant. Israel’s military action against Gaza has nothing to do with retributive justice — in any case a war of vengeance is prohibited. But it has everything to do with a milchemet mitzvah — a war to save Israel from an enemy that has attacked it. The halachic position here (see Maimonides, The Laws of Kings, 5:1) could not be clearer, could it?

Rabbi Goldberg to Professor Alderman Having re-read Tractate Sanhedrin, 73a, I suspect any failure on my part to appreciate what you deduce to be its full meaning is due to the radically different conclusions we draw from its argument about the rodef. In my previous response, I agreed with you about the definition of the rodef and the permissibility of taking preventive action against him. Applying the talmudic principle of reasoning a minori ad majus, I would even concede that this could also be interpreted to apply to those Gazans who actively aid Hamas by ferrying in weapons from Egypt, providing cover and rocket launching sites, etc. But my imagination — let alone a “commonsense reading of this passage” — boggles at your conclusion from it that therefore every citizen who voted for Hamas is a legitimate target. According to most commentators, the popular vote for Hamas was a protest against Fatah corruption and incompetence; not an endorsement of its mad fantasies about destroying Israel and all Jews. In the field of war propaganda, truth is always the first victim. That is why I am less inclined than you to take the dark ravings of Hamas spokesman Fathi Hamad as representative of general Palestinian thinking or mainstream Sunni theology. You may not be interested in the Christian doctrine of “proportionality”, but Israel, since becoming a sovereign state with its own army, has paid great attention to just war theory; hence its concept — sadly tarnished in recent years — of “purity of arms” in warfare.

Professor Alderman to Rabbi Goldberg You may wish to regard the popular vote for Hamas as a protest against Fatah corruption and incompetence, rather than an endorsement of its “mad fantasies about destroying Israel and all the Jews”. I do not. May I remind you that not so long ago many Jewish commentators — including rabbis — chose to regard the popular vote for the German Nazi party as a protest against Weimar corruption and incompetence, rather than an endorsement of its mad fantasies about destroying the Jews? I regard it as a religious obligation not to make this mistake. If the Hamas government of Gaza had engaged only in rhetoric — urging that Jews be killed but not actually killing any Jews — the view you put forward might be halachically valid (though there is room for a strong counter-argument here, in terms of pre-emptive action). But the fact is, Jews have been killed, by the government of Gaza and at its instigation.

Rabbi Goldberg to Professor Alderman Comparing Hamas to Hitler is as emotively exaggerated and logically fallacious as likening the current Israeli offensive in Gaza to the liquidation of the Warsaw Ghetto, as a Catholic cardinal recently did. You dismissed the just war doctrine of proportionality as being “a Christian idea” but not a Jewish one. I could have cited instead Abraham’s argument with God about Sodom: “Will You sweep away the innocent along with the guilty?” (Genesis 18:23). You cite Maimonides on war. Can I remind you that he also provides laws about not cutting down fruit-bearing trees, and only besieging a city on three sides so that its inhabitants can escape, under the rabbinic principle of bal taschit ‘Do not destroy’ (wantonly and excessively).” Peace is Judaism’s most prized ideal. Perhaps you and I should both acknowledge that what is now happening to all Gazans in the cause of legitimately safeguarding Israeli citizens from Hamas rockets demonstrates Israel’s well-known propensity for wielding an iron fist in an iron glove, but brings no credit to Judaism’s ethical teachings.

A fuller version of this exchange first appeared in The Guardian's online Comment is Free belief section. Copyright: Guardian News & Media Ltd 2009