Unfortunately for ethical egoism, the claim that we will all be better off if every one of us does what is in his or her own interest is incorrect. This is shown by what are known as "prisoner's dilemma" situations, which are playing an increasingly important role in discussions of ethical theory... At least on the collective level, therefore, egoism is self-defeating - a conclusion well brought out by Parfit in his aforementioned Reasons and Persons.

Pain and suffering are in themselves bad and should be prevented or minimized, irrespective of the race, sex, or species of the being that suffers. How bad a pain is depends on how intense it is and how long it lasts, but pain of the same intensity and duration are equally bad, whether felt by humans or animals.

Knowing that we can control our own behaviour makes it more likely that we will.

Ancient recipients of instant news probably couldn't do very much about it, for instance. Xerxes would still need three months to get his army together, and he might not get home for years.

More often there's a compromise between ethics and expediency.

...chimpanzees, bonobos, gorillas, and orangutans are thinking, self-aware beings, capable of planning ahead, who form lasting social bonds with others and have a rich social and emotional life. The great apes are therefore an ideal case for showing the arbitrariness of the species boundary. If we think that all human beings, irrespective of age or mental capacity, have some basic rights, how can we deny that the great apes, who surpass some humans in their capacities, also have these rights?

Bush sees the evil as out there in the wider world, residing in people who 'hate freedom'. Look at his immediate response to the pictures of prisoner abuse; this is not what Americans do, these are not our values.