TThis book is about the human desire to experiment with empire. In the past it was done with real soldiers and expeditions and slaves and trade and misery and force. In the future it will be done with generation ships and off-world pioneers, robots and invasion, electronic sheep and people who just don't want to be pushed around any more. Beginning with a discussion of who 'we' are (hopefully, the good guys) and who 'they' are (anyone who isn't us),...