Re: The question I've been pondering for many years is,
If the question is can a species act in the best interests of all species, I'd agree the answer is no.
And, a species could act in it's own interest which may improve things for all species.
However, as you suggest, nations sit like dogs with a bone ready to fight to the death of anyone covets their bone. The good news is that the people who are most afraid of having anything of theirs used for the common good will disappear, too.
And then the carbon emissions will slow down. Undoubtedly the best thing for the planet would be for humans to disappear.