Charles Krauthammer writes with much more clarity on the subject of torture than he does on Intelligent Design. Indeed his recent piece in the Weekly Standard provides excellent insight into the debate over the McCain Amendment.
At the outset he draws some important distinctions between three kinds of prisoners. He distinguishes between the ordinary soldier caught on the field of battle, the captured terrorist, and the terrorist with information. Krauthammer discusses what each is entitled to and how each should be treated.
He also dispenses with the "torture doesn't work" canard and puts McCain's own inconsistencies in his defense of his amendment in bold relief.
Krauthammer is careful to stringently circumscribe both the conditions under which harsh measures should be employed and the people who should be allowed to use them, and his recommendations make a lot of sense. All in all it's quite a good article for someone interested in the moral and practical aspects of the question.
We naturally and rightfully recoil from the thought of employing pain in our interrogations of our enemies. We want to banish the idea from our minds, but Krauthammer argues cogently that in a world in which we are confronted by a mortal enemy bound by none of the rules that have at least partly constrained "civilized" nations, we cannot ban it absolutely. There must, he insists, be exceptions. The real argument should be over what constitutes a legitimate exception.