[a] Some of the information we used to locate OBL was obtained through 'enhanced interrogation' techniques; therefore such techniques really do work.This argument is a mess on at least three different levels. The problem is not that a premise is inaccurate or that some term is misleading; rather, the reasoning does not compute at all. It's counterfeit logic--and a lousy knock-off at that. This is the rational equivalent of a wooden nickel. As the physicist Wolfgang Pauli used to say, “no, no that’s not right--that’s not even wrong!”
[b] Since they work, we ought to accept that they're simply a necessary part of doing business in the rough-and-tumble world of questioning suspected terrorists.
First, (from [a]) it is not legitimate to conclude that a technique "works" merely because it has produced a reliable result in an unspecified percentage of instances. A stopped clock, as they say, is right twice a day. In order to show that a given approach is even comparatively useful, one needs to evaluate its success in the context of alternative approaches. One of the most glaring practical deficiencies of our charitably labeled 'enhanced interrogation' approach is that it consistently under-performs other known methods of information gathering. Individuals under such duress are as likely as not to produce any narrative they imagine might please their captors, irrespective of its accuracy, thereby introducing noise into the communication that's even less productive than deliberate and expected disinformation. Indeed, one of the most remarkable aspects of this whole torture issue is the breadth of professional consensus on the point that it in fact does not work at all. As they say in the South, "that dawg don't hunt." [a] doesn't even represent a fallacy worthy of the name. You want to dignify it with a label like "hasty generalization," say, or "fallacy of exclusion;" but no, mostly it's just lazy, fatuous assertion.
Secondly, the rest of the argument at least purports to rest on that first premise, which is illigitimate; therefore, the sum of the reasoning--even if it were structurally valid--is unsound.
Lastly, and most embarrassingly haywire, is the bizarre disconnect between [a] and [b]. In the fallacy business, this is our old friend Ignoratio Elenchi. The premises are unrelated to the conclusion. The question of whether or not something "works" has nothing necessarily to do with whether it should be deemed ethically acceptable or in any other way desirable. To see how the wheels come off here, we need only consider the same argument with one modification: substitute a different value for the "technique" variable. Suppose it were discovered that whenever we wanted perfectly honest and reliable answers to any question we might think to ask of a suspect in custody, all the interrogator need do is execute his own mother. Quick, simple and efficient! By the flawless illogic of our lovely formula, we should then view such workaday matricide as a perfectly unexceptionable "technique" of interrogation. Its chief drawback might be that you couldn't use the same interrogator twice. Lots of things work. A .44 magnum discharged in one's mouth as an orally administered pain reliever is 100% effective. It's just that the question of efficacy is distinct from the question of appropriateness or desirability.
Clearly, even if [a] were completely accurate on its own, when we combine it with [b], we’ve still got the howling absurdity of that classic informal fallacy to deal with: a premise and a conclusion that aren’t even on speaking terms.
For godsake, QED already…