Everyone in the western world, even non-Christians, has heard the Biblical phrase "God is love". And while that is a true statement, its only half of the story. God is also justice.
A true - and more complete statement - is that God is love constrained by justice, and justice tempered by love. The bottom line is that God is love and justice in equal measure.
That said, I have a serious problem with the death sentence - not because it's unjust or unloving - but because it is so unevenly meted out. Far more people who justly deserve the death penalty avoid it because they can afford the legal representation to skate around it than there are people who are executed. Justice unevenly or unfairly applied is not justice.
Even with that quibble, however, only a morally confused person could argue that Saddam does not deserve to be executed for his many crimes against man and humanity.
"Show me just what Mohammed brought that was new, and there you will find things only evil and inhuman, such as his command to spread by the sword the faith he preached." -Manuel II Paleologus