As I Biblicist, I don’t feel bound by just-war theory merely because it’s traditional. Just-war criteria must be subjected to rational scrutiny. However, since the debate over counterterrorism is often framed in terms of just-war theory, let’s play along with this framework.
i) One criterion in just-war theory is the immunity of noncombatants.
Terrorist organizations exploit this provision by using civilian populations as human shields.
This is a form of moral extortion. A bluff. We dare you to exercise your right of self-defense in case that would result in the foreseeable loss of innocent life.
ii) According to this scenario, nation A forfeits the right to counterattack nation B in case nation A would be taking innocent life in the process—even if nation B deliberately made it impossible for nation A to discriminate between combatants and noncombatants.
iii) However, as one philosopher has pointed out, the logic of that premise can be taken a step further:
Nation A forfeits the right to counterattack nation B in case nation B threatens to retaliate by executing its own citizens:
“Also, your scenario raises the interesting possibility that all Hamas has to do to make Israeli retaliation morally impermissible is to threaten to execute its own people if they retaliate.”
Notice that under this scenario, nation A isn’t killing any civilians. Nation B is threatening to kill its own civilians if nation A dares to defend itself.
Is that a reasonable restriction on the right of self-defense?
This is analogous to a hostage situation in which the kidnapper threatens to execute the hostage unless his terms are met. Should we accede to his demands?
What if this is his demand: unless we execute one of our children, he will execute the hostage.
What should we do in that situation? If we refuse his demand, are we responsible for the death of the hostage?
iv) Isn’t the enemy blameworthy on two grounds?
a) It’s blameworthy for the original provocation (an unprovoked attack).
b) It’s also blameworthy for exposing its civilians to needless harm by using them as human shields.
Hence, (b) compounds the guilt of (a).
v) Thomas Aquinas was an architect of just war theory. However, Aquinas was also the architect of another principle: the double-effect doctrine:
Thomas Aquinas is credited with introducing the principle of double effect in his discussion of the permissibility of self-defense in the Summa Theologica (II-II, Qu. 64, Art.7). Killing one's assailant is justified, he argues, provided one does not intend to kill him. Aquinas observes that “Nothing hinders one act from having two effects, only one of which is intended, while the other is beside the intention. … Accordingly, the act of self-defense may have two effects: one, the saving of one's life; the other, the slaying of the aggressor.” As Aquinas's discussion continues, a justification is provided that rests on characterizing the defensive action as a means to a goal that is justified: “Therefore, this act, since one's intention is to save one's own life, is not unlawful, seeing that it is natural to everything to keep itself in being as far as possible.” However, Aquinas observes, the permissibility of self-defense is not unconditional: “And yet, though proceeding from a good intention, an act may be rendered unlawful if it be out of proportion to the end. Wherefore, if a man in self-defense uses more than necessary violence, it will be unlawful, whereas, if he repel force with moderation, his defense will be lawful.”
Logically speaking, I assume the double effect principle would modify the immunity of noncombatants.
vi) If we treat the immunity of noncombatants as absolute, then just-war theory becomes incoherent. Taken to a logical extreme, the immunity of noncombatants would nullify the right of self-defense. All the enemy has to do to forestall retaliation is threaten to execute its own civilians.
If just-war theory entails unilateral disarmament, then just-war theory is self-contradictory, for just-war theory was predicated on the right of self-defense. It imposes certain restrictions on the right of self-defense, but if the restrictions are so restrictive as to negate the right of self-defense, then the theory is self-refuting.
vii) This, in turn generates a moral conundrum. The enemy can murder your civilians with impunity. You don’t have a right to defend your civilians against attack, for if you do so, the enemy will execute its own civilians.
So, in the interests of sparing the lives of enemy civilians, you expose your own civilians to annihilation.
But why should one set of civilians be totally immune to harm while another set of civilians is subject to total annihilation? How can the same theory promote genocide and the immunity of noncombatants?
[Keep in mind that I’m stipulating to just-war criteria for the sake of argument. The disjunction between combatants and noncombatants is often morally arbitrary.]