Christians for Fair Witness on the Middle East issues the following statement by Rev. Dr. Bruce Chilton, the Bernard Iddings Bell Professor of Religion at Bard College in Annandale, New York:

Why would the State of Israel attack Gaza by air, and threaten invasion on the ground? After all, the target of operations has been the territory that Israel withdrew its forces from under Ariel Sharon, dismantling and destroying Israeli settlements as it did so.

Even as Prime Minister Sharon pursued his policy of unilateral withdrawal from Gaza, his country faced regular missile attacks. Qassam rockets are primitive although highly mobile weapons; they can be fired from portable tripods, but lack guidance systems. Since 2001 civilian centers have been their usual targets, and they have produced casualties and terror without achieving strategic or tactical advantage.

Sharon calculated in 2005 that the crudity of the Qassams, and the promise of Palestinian autonomy in Gaza, would spell the end of the attacks. His calculation proved wrong. The electoral success of Hamas in 2006, followed by its seizure of power in Gaza in 2007, saw an increase in the number of Qassam strikes, as well as in the range of some missiles. For six precious months, Hamas suspended attacks, but announced the end of its truce in December. Qassam assaults have escalated.

In response Israel has targeted Qassam installations, as well as command and control centers and development sites, for sustained bombardment and destruction. International reaction against Israel -- especially from Christians -- has been more negative than the censure of Hamas for its attacks. Israelis have been accused of "disproportionate" military tactics, especially because civilian causalities have been involved. Much public criticism of Israel ignores Israeli withdrawal from Gaza, overlooks the Qassam attacks, and promotes a false moral equation.

How much force is warranted in response to an egregious wrong? Unless a realistic answer to that question can be found, violence spirals through the self-righteous atmosphere of revenge. During their often violent histories, Judaism, Christianity, and Islam have demonstrated a tragic capacity to unleash reprisals against one another, using martyrdom as a means to motivate their adherents to persist in war whatever the cost. Nation-states that have inherited the cultures and the languages of the Abrahamic faiths have shown themselves no less addicted than their religiously motivated predecessors to putting their people in harm's way in the alleged national interest.

Proportion in war might seem an oxymoron; warfare represents the failure of proportionate means. But when violence overwhelms the give and take of healthy relations, how can a way back to health be found?

One measure of a policy is its purpose. In the cases of Hamas and the State of Israel, what is the aim of Qassam attacks on the one hand, and of Israel's attacks on Gaza on the other hand?

Qassam rockets are deployed by their namesake, the Izz ad-Din al-Qassam Brigades, the armed wing of Hamas. Fired over the border between Gaza and Israel at civilian centers, they put into action the stated aim of the Hamas Charter of 1988: "Israel will rise and will remain erect until Islam eliminates it as it had eliminated its predecessors." By intent and impact, Qassam rockets terrorize Israeli civilian populations in an attempt to galvanize action across the Muslim world in order to eliminate the State of Israel.

Israel's attacks in Gaza involve civilian casualties, although that is not their purpose. At every stage -- deployment, preparation, and design -- Qassam are in such proximity to residential populations that even well targeted strikes bring calamitous results. But the aim of Israel is not the elimination of Gaza, but the end of Qassam attacks. The willingness of the Israeli authorities to halt their attacks in the hope that Qassam sites will be dismantled is a positive development.

War is an obvious evil, an unmistakable sign of human sin. Yet even in the case of war, humanity can be served by the aims that are set and the means employed to achieve those aims. As a war aim, the elimination of the State of Israel is morally abhorrent. Likewise, the means of Qassam rockets can hardly be justified; their only virtue is their lack of accuracy. Israel's aim, the cessation of Qassam attacks, has been accompanied by a continuation of humanitarian aid. Moral equations in times of war are parlous, but the best outcome now seems to depend upon the resolve of the State of Israel to maintain a limited war aim, and the willingness of the governing authorities in Gaza and their allies to find a way to affirm Palestinian autonomy without insisting upon the elimination of Israel. That proportion of restraint and flexibility, rather than the disproportionate assignment of blame to the supposedly stronger party, is the last best chance of avoiding an escalation of violence in the Middle East that no nation on earth can afford.