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But he isn't worth nothing. When you say so you negate the whole reason to object to torture in the first place, which undermines not only your entire point, but also all of humanistic morality. If this guy can be used as a means to an end (setting an example, as you say), because he did something bad, then so may the 'actual bad guys' held at Abu Ghraib be tortured or killed as a means to an end... which, in fact, they were. This guy is in prison for doing it to them. What you've got there is an animal eating its own legs.