C.S. MacCath

In an earlier stage of our development most human groups held to a tribal ethic. Members of the tribe were protected, but people of other tribes could be robbed or killed as one pleased. Gradually the circle of protection expanded, but as recently as 150 years ago we did not include blacks. So African human beings could be captured, shipped to America and sold. In Australia white settlers regarded Aborigines as a pest and hunted them down, much as kangaroos are hunted down today.