A roughly agreed upon morality, in that sense.Well, sure. Morality can be just as subjective so on that score it's not superior; it's a wash. And that's why a democratically based system for resolving those issues is used. After all, the maintenance of a civil society requires a certain amount of buy in from the general public and a democratic system helps provide that.
But you believe a civil society and the general welfare as defined by the Founders to be a good thing. That's based in your morality.IMO, the decision as to which rights to protect and which not should be based on its' effect on the maintenance of a civil society and the promotion of the general welfare. There's no "magic formula" that can be used to tell us for certain where to draw the line. That's why we have a political process.