Why We Shouldn't Be Critical of Saddam's Hanging

On December 30th 2006 Saddam was hanged to death. This followed conviction that he was behind the killing of many Iraqi's over the attempts of his assignation. The question here is whether his execution is justifiable or not.
The hanging of Saddam has elicited the old debate on whether it is justifiable to show the world the killing is bad by killing the killer. But according to me (I am not attempting to justify the hanging of Saddam, but just sharing my mind out) hanging a criminal who deserves capital punishment is justifiable.

Capital punishment is justifiable for one major reason; the elimination of a killer. Killing a criminal does not mean that you are trying to prove to the world that a criminal deserves such punishment, but on the look of things, a capital punishment entails a process of ensuring that such a person is not allowed to flourish and continue killing others. The society is simply trying to develop laws and means whereby those who are cruel and unjust as Saddam are eliminated.

There is also the argument that capital criminals should be confined in prisons forever. This argument is plausible but I don't think that anyone deserves punishment like that. Even the laws that have been enacted to confine people in prison for life are not human. The mental torture that you will never be free until the day you die is just too much. Instead, a person who is guilty of life long imprisonment should be either given the death penalty so that he is relived of the agony more painful than death itself.

And the bible agrees. God himself endorsed capital punishment to capital offenders. The method of execution was public stone throwing, whereas the Romans endorsed the cross. And the capital punishment that God shall execute upon all non believers is the complete destruction by the eternal fire that will consume all sinners forever and forever (until there is neither sinner nor sin anymore).