I rejoice that our government executed justice to this man. We tend to read only small sections of the Old Testament, the parts devoid of anger, calls for justice, and complaints to God. These emotions are too raw, too real for many Christians who believe Jesus brings only joy, even in times of deep trouble. Instead we stay in the easier sections, ones where God is praised ceaselessly. This stunts our spiritual growth. Passages such as Prov. 11:10 and 21:15, relevant to this situation, give what actually goes on in a person and a healthy response when the wicked are punished. To stay these feelings are out of bounds because "I was once an enemy of God" is simplistic and reductionist. I am not the same as an unrepentant murderer.
I can pray for my enemy to repent and rejoice in justice for the wicked. To put it succinctly, I pray he will repent but rejoice when he is brought defiantly to justice. I do not see how these are mutually exclusive. A Christian can do both.
I do not want to defend those who gloat about Osama bin Laden's fate. I do not wish for him to "burn in hell" for eternity. Thank God (literally!) that this is not my decision.
I believe our witness is diminished when we deny that feelings of anger and calls for vengeance can be directed to God and feel guilty when the wicked are punished. It makes Christianity seem aloof and detached from real life. Christ did not die so that we could turn off our emotions and when we die go to a disembodied oasis of pleasure. He died so we could be in relationship with God, the church and the world. Those who violate this relationship are punished. I am saddened that Osama bin Laden never knew the God I love and serve and repented of his sins. But I have joy that this man has paid the price for his actions through our just government.