You and I agree more than we disagree. We agree that the prisoners on Guantanamo need to be treated humanely; we agree that crafting a policy toward these detainees should not be ends-driven (i.e., "under-what-set-of-laws-can-we-torture-them?"); and we agree that terrorists can be classified as somehow "different" from lawful combatants. We also agree that the Geneva Convention, as originally drafted, may not have contemplated this kind of "other" soldier: one who would not lay down his arms after an armistice, for instance. Your contention is that the convention therefore does not apply to this "other" class of soldiers. Mine is that the Geneva Convention both can and must apply, even to them. Why? Because the convention itself purports to control in "all cases of declared war or of any other armed conflict … even if the state of war is not recognized by one of them." The Geneva Convention controls, even when one party is not a signatory. It controls even when the United States is fighting an undeclared war. Why? Because these are the rules of war, even when individual parties don't acknowledge that wars require rules.
You have advanced a possible framework for what these new rules of war might be, rules that depend on creating a new classification for something that sounds like "a terrorist." And you want to define a "terrorist" as someone who targets civilians. My objection remains the same as before: Your criterion for this "other" kind of soldier/terrorist is both over- and under-inclusive. It's over-inclusive because it sweeps in any lawful combatant who reasonably targets civilians (what we've called the "Dresden" problem), and—your hope that those days are over notwithstanding—I am not convinced that there will never be a strategic reason for us to target civilians again. Your definition is under-inclusive because on your theory, the al-Qaida bombers who targeted the World Trade Center are terrorists, while those who went after the Pentagon were lawful combatants.
You and I are not the first to recognize that "other" kinds of soldiers—soldiers not contemplated by the Geneva Convention—exist. In 1977, Protocol 1 Additional to the Geneva Convention was adopted to address the problem of combatants (usually in "wars of liberation") who don't wear uniforms, carry weapons openly, and thus don't come under the protections of the Geneva Convention. But the United States refused to ratify Protocol 1, because, among other things, it gave POW status to combatants who distinguish themselves from the civilian population only "while they are engaged in an attack or in a military operation preparatory to an attack" (Section 44.3). In other words, under Protocol 1, terrorists can blend into the crowd, whip out a weapon, and attack with impunity. This, quite reasonably, strikes us as not being fair.
Protocol 1 was intended to—to use the politically correct construction—validate different kinds of wars. "Wars" are not just about my tanks versus your tanks. They are now also about your freedom fighters and guerrillas too. There need not be a declaration of war, or a uniform, a battlefield, or even a coherent enemy. Check it out: Protocol 1 sought to make unfair wars fair. This was my point from the outset: "Rules of war" are inherently illogical. Maybe they made sense in some Western, imperialist Henry V past. (Remember, tea served in your tent, messengers to-ing and fro-ing, camping out all night under the stars, and waging polite battle at dawn?) But terrorists refuse to abide by those rules. They refuse to abide by any rules. So trying to set up rules for them is bizarre. All we can do is set up pretty universal rules and try to hold ourselves to them. We have those rules: the Geneva Convention.
You still haven't told me what you would have done to these al-Qaida terrorists that can't be done under the convention. You mention interrogation and repatriation. We can still interrogate under the convention. We can also try them as war criminals before repatriating them. We can also do what we're supposed to do under Article 5 of the convention and allow "their status [to be] determined by a competent tribunal." If we're doing away with POW protections, at least let's have some logical basis for it. If you think suicide bombers are going to be deterred by lesser protections if captured, you might want to recall that they are, after all, suicide bombers. I just don't know how well deterrents work on someone whose ultimate goal is death by fiery flames.