Death is no penalty

The trial of Zacarias Moussaoui seems set to become the best demonstration yet of the utter futility of the death penalty. What use is it to execute someone whose goal is martyrdom in any case? Its like letting him off scott free. And it certainly won't be any use as a deterant to anyone else planning a suicide attack. And this is all without addressing the ethical issues, namely its wrong to kill someone who is at your mercy.
The problem I have with executing people like this, aside from the fact that its barbaric, is that it is counter productive. These people are meant to represent a threat to our civilisation, so study them when you have them. This goes for Saddam as well-people like him keep cropping up throughout history causing mayhem-once he's in custody and no threat to anyone why not take the opportunity to find out what makes him tick? Know your enemy. Its common knowledge that the psychological profiling of Hitler during WW2 proved invaluable, killing someone like this just seems a waste. And if we want a world where human life is respected more than it is now, executing anyone is counter productive.
Now I'm going to get on my big English high horse and say that America needs to catch up with the rest of the civilised world on this issue. But polls (gallup) suggest that there's still widespread support for the death penalty in the states-somewhere around 70%. Then again support for the penalty over here seems to have only just dropped below 50%; the lowest level since it was abolished. Still higher than I'd have thought. So maybe I'm wrong.
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