The "solution" being offered to this double bind by certain ideologues - "it's not torture, just a necessary tool in the War on Terror" - is not a solution that can be accepted while retaining honour.
How much history and how much myth are codes of chivalry and honor? and, would you consider certain acts as practiced in the past, considered within honorable and chivalric codes, to be honorable and chivalric today?

I am not, by any means, supporting torture nor am I discarding the idea that we must act and appear more honorable and humane than the enemy. Particularly in COIN. Nor even advocating a regression to some form of total war on the population.

But, I would challenge you all directly to point to a historical victory that was won through and honorable or chivalric act. I don't mean the last act where a leader accepts the parole or sword of another with honor and chivalry, but that the battle or war itself was predicated on such acts. I think we could name a few defeats or really horrific death tolls that occurred because an act of "chivalry" where the survivor of such an encounter returned to destroy the offerer.

They say that "war is hell" for a reason.

Historically, chivalry has been discarded out of necessity and honor conferred to the winner. Chivalry has often been limited to a small group or class. Everyone else being fair game. So, let us not confuse our modern ideas of chivalry and honor in military groups or individuals with history or actual war.

Having said that, I would point to something I wrote a few years ago (pardon the self linkage) re: chivalry today and the art of war. Quoting Shay:

This brings us back to my earlier line of reasoning. It is not enough to ask, “Can our warriors still get the job done if they do not have a code?” We must also consider the related question: “What will getting the job done do to our warriors if they do not have a code?” Accepting certain constraints as a moral duty, even when it is inconvenient or inefficient to do so, allows warriors to hold onto their humanity while experiencing the horror of war — and, when the war is over, to return home and reintegrate into the society they so ably defended. Fighters who cannot say, “this far but no farther,” who have no lines they will not cross and no atrocities from which they will shrink, may be effective. They may complete their missions, but they will do so at the loss of their humanity.[snip]
Therein, I believe, lies the question that must bother Luttrel. In the end, the two concepts of chivalry actually collide. The first part that demands we treat our brothers in arms with honor, defend them, bring them home, etc and to do no harm to others who also fall within the code.

Which one was the most important to have followed? Which one is the most cruel? Which one the most damaging?

Luttrel doesn't know and that is why he still wrestles with it today.

I would say, as others have, it is all good and well to talk in ideological terms here, even so far as intimating the lack of honor or chivalry in various others, but I would guess that each person would be tested under different circumstances and would come to the same dilemma in the end, which ever he or she chose, finding themselves wanting.