Where did I ever say anything about a universally-held moral precept? I believe I have stated several times in this thread and in the politics thread that morals are what a society determines, either based on a belief that a Divine Being has deemed them as such, or because of the idea that it is "functional to society" or "not functional to society." The concept of "Thou shalt not kill" has become a universal law in all nations, with exceptions that differ based on the various societies' understandings. Nevertheless, it is based on a moral. But if we truly believe that life should be preserved as often as possible, then we should not limit that belief simply because of another person's "right to choose." Every other exception is based on a much more extreme and rare set of circumstances.

What is functional to society is clearly too loose a rule to devise a legal system. A society could conceivably function with almost no laws at all, though drastically changing to such a society would be destabilizing. But because of morals that much (not necessarily all) of that society holds, we devise laws to protect them. Societies we see today as terribly immoral were once quite stable. But as we see certain other things as right, we choose to reject their systems and devise our own based on our own principles. A majority of my society feels that abortion is wrong in some or all cases. But in the name of "not imposing morality on others," a minority gets to kill literally millions of children every year.

And ultimately what is the reasoning? in literally over 90% of the cases, it is a reason easily bundled under the heading "INCONVENIENCE."