There are some particular moral truths that I believe we have access to (such as the one not to inflict pain on a sentient being for no reason).
Utilitarianism condones killing of innocent human beings, even murder, if it makes the world a better place.
What we need is legislation, not negotiation, for the entire globe.
Global governance need not take a democratic form.
According to deontology it is wrong to kill an innocent human being, period.
Being a moral realist I see normative ethics as a search of the truth about our obligations and a search of explanation; the idea is that moral principles can help us to a moral explanation of our particular obligations.