It may be tempting to believe that humans have become more just, and that any incidents of supremacy thinking will eventually disappear. Environmental threats like climate change present themselves as new problems that have little to do with our conventional concepts of morality. I argue that the belief in the supremacy of all or some of humanity has set us on a path towards environmental collapse much as it has enabled our accomplishments. Moral philosophy itself has systematically reinforced supremacist preconceptions and has arguably led us to accept unsustainable behavior as normal. Understanding the moral justifications that we have constructed for supremacist thinking and their impact on our biosphere may be central towards preventing environmental decline or collapse.