Unless you’ve been living in a cave these past few weeks, you are well aware of the renewed fighting between the Israeli Defense Force (IDF) and Hamas that has been going on for the past few weeks. Now, keep in mind that while I once supported the just war tradition, I do not support the tradition and have not for some time.
I also want to state that this post is not an endorsement of violence by Hamas or by the IDF. Both sides are to blame for this current escalation of violence and both sides have innocent blood on their hands. But, at the same time, the idolatry of the Christian Zionists is almost unbearable!
The Just War Tradition and Noncombatant Discrimination
Hamas is to blame for any civilian casualties in Gaza.
It seems to me that Todd does not understand the just war tradition’s principle of noncombatant discrimination. He effectively bastardizes the principle by shifting the blame off of Israel.
Let me back up here for a minute. There are two sets of principles one must consider in determining if a war is “just.” The first is Justice in Going to War (Jus ad bellum). These principles rightfully understood, guide when a nation is justified in going to or waging war with another nation. The second is Justice in Waging War (Jus in bello). These principles are meant to guide the nations while at war. The principle of discrimination falls under the Jus in bello principles.
It is common today for Christians to use the just war tradition as a sort of public policy checklist. That’s where the bastardization of the tradition comes in. Here, the tradition is weakened to say that noncombatant deaths are permitted “so long as that harm is not unintentional.”  So Israel didn’t intend to hurt civilians and so they were justified in firing missels into populated areas. That’s a giant load of bs!
If we want to look at the just war tradition from a Christian discipleship perspective, the principle changes a bit. Here the principle
does not grant permission but rather names a positive responsibility, born of love for the neighbor, to actively strive to protect noncombatants from harm while waging a just war…It is not enough that just warriors do not intend the death of noncombatants; they have a responsibility to exercise due care in avoiding noncombatant deaths and protecting them from harm. 
So, if we are to take the just war tradition seriously, Israel must be held accountable for the civilian deaths because they did not take due care to avoid civilian deaths. To put it another way, Israel is waging an unjust war!
The Just War Tradition and Proportionality
The proper understanding of the jus in bello criterion of proportionality, that for centuries was part and parcel of customary international law has to do with the unintended, “incidental” or “secondary” harm done to noncombatants. Proportionality has to do with weighing the unintended bad effects to noncombatants against the intended good effects of an attack.
First off, it sounds like Keith is blending some of the principle of noncombatant discrimination into his definition of proportionality. As Daniel Bell points out, this is par for the course when one takes a public policy approach to the just war tradition.
To begin with, the criterion of proportionality does not receive much attention in Just War (PPC) because it is thought that proportionality has already been adequately explained in the course of treating the other criteria: under reasonable chance of success, where the costs and benefits of a prospective ware are considered, or under discrimination, where the benefits of an attack are weighed against the unintended harm done to noncombatants. 
When we look at the just war tradition from a Christian discipleship perspective, again, the principle of proportionality changes.
According to Just War (CD), the criterion of proportionality means not only that just force is directed at the just end of war but also that it is measured force, in the sense that it is limited to the amount of just force necessary to attain that just hand. Having the right to go to war dose not mean that one may unleash all possible force and destruction on the enemy, The criterion of proportionality rules out the application of maximum force and the sentiments that underwrite such disproportionate force, such as “the crueler war is, the sooner it is over.” Proportionality as a distinctly Christian discipleship calls for the use of the minimum force necessary instead of the maximum allowable. 
I disagree with Keith that proportionality “has absolutely nothing at all to do with bringing a gun to a knife fight.” But when your version of the just war tradition is a watered down public policy checklist, that is to be expected.
Again, Israel is waging an unjust war by basically carpet bombing the hell out of Gaza.
 Daniel M. Bell Jr., Just War as Christian Discipleship, (Grand Rapids: Brazos Press, 2009), 213.
 Ibid., 213.
 Ibid., 227.
 Ibid., 228.