Hm, I don't think I was setting up a trap for
@Pin, just exploring various possibilities. In a earlier post, he does justify the non-immorality of killing puppies by stating that they are not "special" compared to other species in the way that human beings are. It being implied that what would make it immoral to kill a human being is tied to what makes a human being "special". Which is potentially a completely acceptable position, I think, though it does require specifying the content of that "specialness". It is not enough to claim that
homo sapiens is special without detailing in what way.
Just to clarify, I didn't put forward this argument as mine, but as an illustration of what may be argued by a defender of the idea that it's not immoral to kill puppies, or any other being that is not human. I wouldn't embrace it, personally; I just put it forth as up for being debated and pulled apart, and I think that you do a good job of showing what is problematic about that line of reasoning. (In fairness, Pin also did). The premise that morality is connected to self-consciousness is definitely not an obvious one, in my opinion also; but I think, intuitively, that a good argument for it might be made, though various definitions would have to be established first, etc. I kind of just assumed that the argument had been virtually made, and embraced the premise following up from that.
I think you're also right that it does not follow from the fact that animals do not "moralize" in the same way that we do, that they have no morals; and even if they truly had no morals at all, it would not evidently follow that human morality should exclude them from its purview. An interesting question here might be: if human morality does include them, how would it? In the climate example that you give, we can at least tie it back to the idea that polluting the planet might ultimately lead to our
own demise, that is, the disappearance of humans. So in a way, we would tie it back to ourselves. Can we do this in the case of puppies?