The debate before the court and before the country concerns the standard that should control us and our lower nature. We have laws because not everyone would do the right thing (whatever that is in our relativistic age) were they not compelled to do so. How many more people would cheat on their taxes if there were no penalties?
This battle to hold the moral line has been lost because the culture is no longer responsive to ancient beliefs and teachings due to our primary pursuits of wealth and pleasure. Among the several problems with this departure from commandments and laws that sustained societies for at least two millenniums is that all things now become not only possible but probable. Having ignored true North, we are unable to tell where we are or to navigate out of troubled seas.
It isn't just homosexuality. I know some very stable, kind and loving homosexuals. I know some dysfunctional, divorced and abusive heterosexuals. Some homosexuals probably make better parents than some heterosexuals when it comes to care, love and support.
But (and this is what Santorum was getting at) who gets to decide moral questions when they intertwine with temporal law and based on what standard? If the Texas sodomy law is struck down (as it probably will be), then it is fair to ask, what's next? To feign outrage that Santorum would mention these other practices because some might find them offensive is to ask on what basis? Would the Supreme Court be wrong to strike them down, too, should they be challenged? If they were challenged, on what basis of law, reason, logic, theology or precedent could any objector then object?
See what I mean about moral dominoes?