Good reading, via The Dodo:
All of these human and nonhuman beings suffer terribly. All of them are worthy of our compassion. I have always wanted to help them all. I still do. But the reason I choose to dedicate the majority of my time to advocating for nonhuman animals rather than all of those deserving humans is that we as a society all basically agree on human rights.
When I say we as a society, I do not mean the moral outliers of the international community like members of ISIS, or those in our own society like rapists or serial killers, but those who represent the dominant ethic in the world community, the law abiding members of our society and the international community. And according to that dominant ethic, it is wrong to abuse woman and children. It is wrong to murder innocent men. When we see humans who are starving or being exploited, raped, kidnapped, murdered or tortured, we believe it is wrong. Most governmental bodies around the world, non-government organizations (NGOs), and individuals agree that it is wrong to cause intense physical or emotional pain and suffering to human beings. We criminalize such harm, and we punish those who commit these crimes.
The same cannot be said of animals, especially not farmed animals, whose abuse is accepted by the same moral community that rejects the abuse of humans.