Is capital punishment acceptable in our advantage societies?

After hearing about the death of Bin Laden and seeing how many people came out to the streets cheering on the deadly acts of the American government, I just want to know how other people feel. Let me make it clear by NO MEANS am I condoning what Bin Laden has done but I do question our beliefs in humanity. As we praise ourselves on being well ahead of more primitive societies how much of this praise do we deserve? Why are we so vengeful? Why do we have so much apathy? Why do we blindly follow what our governments say and do? Just for a reminder; we live in democratic societies our politicians should be scared of us not ignorant of their constituents.