Hullo Again Scott,
I gather you and I have switched from a positive discussion about how to legally classify the detainees held at Guantanamo to a normative discussion about how some not-yet-invented corpus of international law might classify them.
I have to tell you I'm loath to shelve the pragmatic discussion about how to classify the 158 detainees, and here's why: 1) The military needs a coherent, existing, internationally accepted set of procedures for how to treat the detainees, and it needs it two weeks ago (it also has one—the Geneva Convention); 2) as signatories to the Geneva Convention, we are bound by the convention's presumption that the detainees are POWs until a legal determination otherwise can be made on the merits; 3) I can't for the life of me fathom what else we might want to do to the detainees—starve them, poke their eyes out, torture them for the sheer vengeful joy of it—other than accord them basic POW privileges. Charles Krauthammer recently pointed out that we must reserve the right to interrogate/torture them, but the need to obtain military secrets from terrorists is no more compelling than the need to interrogate lawful combatants. And under the Geneva Convention, we can still interrogate; we simply have consequences to face. 4) (And this point's been made eloquently by Colin Powell, half of every op-ed page, and a good many "Fray" posters.) We must abide by the existing, nontheoretical Geneva Convention because we want the enemy to do the same. Pretextual or not, one of the original stated reasons behind the kidnapping of reporter Daniel Pearl was the treatment of Pakistani detainees at Guantanamo. I'm not arguing that Pearl wouldn't have been kidnapped otherwise. I am saying that the mere appearance of even debating whether accepted norms of international law should apply is disastrous: If the world thinks we have declined to abide by the existing rules of war, the world assumes all bets are off. Our soldiers, if captured, are dead.
I guess I am therefore saying, in response to your purely theoretical point, that even if we could cook up some more apt, post-Sept.-11 rules of warfare, the reason the Geneva Convention should still apply is that it is accepted as a pretty universal baseline. Even crazy-violent Somali warlords respected these basic norms enough to give POW status to the downed American pilot they captured in 1993.
This leads back to your main premise, with which I must continue to disagree. The evidence that the rules of war exist primarily to protect civilians just isn't there. The fact that one of the four Geneva Conventions of 1949 expressly protects civilians or that all four of the conventions mention them doesn't signal that the protection of noncombatants is the primary or driving goal of the conventions or a basis for distinguishing "just" warriors from the unjust ones. To read that out of the other three conventions—which seek to regulate treatment of "the Wounded and Sick in Armed Forces in the Field," "the Wounded, Sick and Shipwrecked Members of Armed Forces at Sea," and the "Treatment of Prisoners of War"—is kind of like reading the Second Amendment and then saying the entire U.S. Constitution exists only to protect the right to own guns.
And I won't be able to look myself in the mirror for making a legislative history argument—although it might win me that coveted clerkship with Justice Scalia—but the original purpose of humanitarian law in wartime was to protect the wounded and sick combatants. This is what animated Henri Dunant and led to the drafting of the first Geneva Convention in 1864. Why? Because it makes no moral sense to gratuitously punish the wounded and the captured, who can no longer harm you. You can certainly advance the argument that what distinguishes legal combatants from illegal ones is whether or not they target civilians. But I don't think you can support your point with the Geneva Convention.
I am not against protecting civilians. I am not for, as you say, "reverting to Dresden" (although I maintain that so long as any civilian is targeted by the U.S. military, your definition denies our soldiers POW status). I am arguing that the rules of warfare must be broader and more generous than your stated purpose: They must ensure that every aspect of warfare achieves at least some basic respect for humanity, writ large. The way in which terrorists target civilians reveals their wholesale lack of humanity. But the rules of war principally exist to ensure that regardless of what we are faced with, we retain ours.