God is Not Great, by Christopher Hitchens

Today I was in Borders and saw a hardback in the new realease section. The title, God is Not Great: How Religion Poisons Everything. I picked it up and thumbed through it. I didn't buy it, not yet. I read the back cover and the endorsements. One stood out, it's from the New Yorker and praises Hitchens as "An intellectual willing to show his teeth in the cause of righteousness".

I would love to talk with the person who wrote the endorsement and ask them not only how this book serves the cause of righteousness, but what they think righteousness is. Apart from God, I can not conceive of righteousness, and every attempt to define righteousness apart from God seems to me to fall flat on its face.

The most common definer of 'right' apart from God is usually a sense of commonly held norms. What a community deems to be right is what defines right. Even on the surface, this is flawed. What about the indigenous tribes of Bolivia that, until recently, buried twins alive because they thought they were evil. It was the norm. It was deemed right (to keep them alive jeopardized the well being of the tribe - it was for the good of the group that this attrocity was justified). On such a reasoning, racism in the south was right, if the majority agreed it was right.

No, there must be some greater definer of right/wrong, good/evil than a communal sense of it. But what is it? Can anyone make any case for any definition of 'righteousness' apart from God?