It is a bit of a conundrum isn't it? I'm not terribly convinced that we need rational justification to make some idea of belief a part of the public square... After all relationships are also part of the public square, and are based on emotion and feelings, gut intuitions, that clearly people don't all share. And no doubt these relationship affect others directly and indirectly, postively and negatively.
But relationships aren't quite as encompassing as religion is. In fact few if any systems of beliefs are.
But I think we're looking at it from the wrong perspective here... Science can tell us about the world, but has no real business applying values to the world. It can tell us whether or not fetuses are alive, or even human, (yes in both respects) but they can't tell us whether or not they are persons, or morally valuable entities. It seems like we need a value system for that, which philosophy or religion can help supply. Now whether or not there are good reasons to choose religion over philosophy may just as well kick religion to the curb, but if viewed from this perspective, religion has, at the very least, some measure of legitimacy in the public sphere.

I have to agree that it is the sense of entitlement, and totalizing nature, of religous belief that is problematic within the public arena. That and the issue that, despite those totalizing beliefs, there is in fact far more than one group claiming religious truth extant in our world. But even beyond those issues, if everyone who subscribed to faith could be lined up in agreement, where would that leave the atheists and agnostics? Should they suffer the tyranny of the majority on issues of moral law?
In the U.S. we have a constitution that clearly divided the chuch and state, yet those framers were the product of a society that for much of its brief exisistance held membership in the Christian church to be a requirement for sufferage. It was their rational choice to leave their faith at the door. It seems to me that both faculties served them well, at least in this regard.
Because moral and ethical belief sytems are so dearly held and so much a part of self definition, no one is likely to give way quietly when considering the enshrinement of a religious belief contrary to their own into the arena of public law. Yet if I as a rationalist wish my ethics to be reflected and respected in the character of our law and public debate, can I doubt that those supporting faith based ethics have any less desire or right?
It seems that in public policy a bias toward reaching consensus through debate, while not giving any one group or belief a true voice, gives a more livable result than looking for a single faith or reason based answer to moral questions in the public realm. In the end, while faith based dialogue deserves some space within political moral debates as the personal belief of those making the arguement, it earns no place in and of itself as dogma, and should yield no greater sway than any arguement based on reason held as personal belief.

Well, religion clearly *does* form a valid basis for public reasoning. Regardless of the logical sense of any such argument, clearly a great many people /give credence/ to such arguments. That, really, is the only thing there is - politics is persuation. However, I think it is equally true that any particular view (say, free will, or whether to eat meat) is held and held against by religious people. Essentially, while people *claim* a religious basis for their position, it is not an objective basis. Many Christians hold opposing views, therefore Christianity does not imply any fixed opinion on those issues - rather they come from the interpretation of the people themselves.
Once that is established, we must simply look at whether people are using religion as an excuse for holding a particular view, or whether like most people, it is just another crossroads in their web of beliefs.

Just to respond to Tennessee...
I don't think its entirely fair to say that the theist is inconsistent amongst themselves, which shows that ethics is non-objective.... Because ethics IS non-objective. You cannot derive an OUGHT from an IS as Hume points out so succinctly.
Moreover many of the ethical issues that we face today have no recommendation from the Bible, so it seems that there is no reason for consensus amongst them.

This is a timely topic for me. I've been trying to find a way to think about those who, through political action, work to impose a religious ideal on people who may or may not be in agreement with that ideal. An analogy I thought might apply is that the politically active religious believer is to those who don't agree with them like a criminal is to a victim. The criminal, either deliberately or without thinking, ignores the humanity of the victim. Does it seem as though the religious in the public square are ignoring the humanity of the non-believer, or even perhaps demonizing them? And can we also extend the analogy: does the non-believer do the same to the believer? If this is true, why do we do this to each other? Would it be because we want to discredit and discount the other's ideas and ideals so we can ignore them completely in favor of our own? Maybe that is perfectly normal. But even if it is normal, is it conducive to peaceful coexistence? If this analogy is seen by many to be true, perhaps we could create a less fractious and more civil society by acknowledging this tendency within ourselves, whichever side we are on, and thereby begin to contain our desire to overcome all others by remembering that in fact they are not demons or even strangers, but instead are people like us who have ideas that need to be heard by all so that we can have a society with a solid basis in democracy that allows for all to be heard and a true consensus to be built from that basis. Does this make me a hopeless optimist?

It may well be that if you assume religion to be irrational you get the result that the totalizing elements of religion should be kept out of the public square, but it's worth recognizing that such a conclusion is still only conditional. If these totalizing beliefs are rationally held, then why shouldn't they have a place in the public sphere?
I think in the end most people's moral intuitions are what guide them in approving or disapproving of public policy. For some people, those moral intuitions fit into a religious framework. For others it doesn't. Except in the case of the extremist who will never question any beliefs, the totalizing effect just doesn't seem to me to be present. I consider myself an evangelical Christian, and I consider the Bible to be without error (once it's made clear that figures of speech, rounding of numbers, poetic imagery, and so on can count as making statements that aren't in error). Yet I've changed my mind lots of times on plenty of issues, including ones at the center of philosophical debate, particularly in ethics. I think, therefore, that your insistence that religion leads to this totalizing effect is just insensitive to the facts about what religion requires of someone.
Philosophile: I don't see how Hume showed anything. His argument is at best question-begging, since the conclusion can only be true if something like emotivism is right. Utilitarians believe facts about happiness and unhappiness ground moral truths. Social contract theorists believe facts about what rational people would agree upon ground moral truths. Virtue ethics takes facts about what makes someone a good person to be the ground for truths about moral action. Even a simplistic subjectivist view grounds the truths of moral statements in facts about the speaker's attitudes. Virtually every meta-ethical view grounds moral truths in some facts. Only if moral statements have no truth value (as Hume thought) or if they are true for absolutely no reason (which I've never heard anyone defend) will Hume be right. I happen to think both of those options are pretty ridiculous, but if those are the only views on which his argument will work, then it seems to me to beg the question against all the other views.
In any case, pretending that Hume's argument works only against divine command theorists who base morality in God's commands is just to miss how amazingly radical Hume's statement is. It completely defies commonsense morality.

I am out in the cold here.
It seems to me that somehow we need to bring humanity to a conclusion that is mutually acceptable to all of humanity. Religious belief seems to fail both the cultural and the individual when dogma takes the place of mystery. Belief in God seems to stem for repressed childhood impressions. As a small child adults are not only ?giants?, they can as well perform ?miracles?. This suggests that each and every individual human will look for something outside of themselves to ?protect? and take care of them. This creates a problem if these individuals, looking for protection outside of their own selves, are indoctrinated into a belief system that not only guarantees community in the here and now, but as in Christianity and Islam, provides protection in a mythical ?afterlife?. Individuals that need to feel protected will turn to existing religions or will create new religions to gain that ?feeling? of protection.
There is and will always be a great number of mysteries and unanswered questions.
This we know;
We exist on a planet we call Earth in a galaxy we call the Milky Way, part of an ever expanding universe.
There are laws of nature that have been discerned by wise men that always and everywhere hold true.
There are things that are good for humans, intelligent mammals, and things that are bad for humans.
Joseph Campbell suggested that a new mythology that encompasses the whole Earth and the entire human race is what is needed to get us past our petty differences.
Perhaps there is a definition of God that all mankind could agree on?
God is the Creator. It really does not matter how or why, creation exists.
God is within and without. (ie. God permeates reality, turn within and find God or turn outwards and find God in the beauty of nature.)
God set the natural laws of the universe by which all things abide. If we do not understand something it is because our minds are, as of now, inadequate. God gave us the intelligence to decipher reality so we should attempt to.
The Earth, made by the Creator, provides for us and protects us. (Atmosphere blocks gamma radiation)
God is the giver of life. Life is granted by God.(Man can manipulate life but not create it, except through procreation.)
Looking at God this way solves the fundamental problem of defining that which can never be defined, God.
This way of envisioning God as well will cause a new respect, as all is of God, disrespecting or abusing any part of the natural world is defiling the body of God.
I suspect that many, many ?religious? individuals cling to their respective religious dogma but do not actually ?believe? it, ?seeing? something of value but without understanding.
This statement comes from a reading of all those deep thinkers, many considered, religious that accept that there is something beyond their selves that can not be defined by the dogma of their respective organized religion.
Well, naturally, if every one could see the sublime simplicity and beauty of this definition then we might have peace on Earth. But then those in power would lose their power and, naturally, the awakening of mankind?s soul would not allow them to control their fellow man as they do now.

Ken,
What if I told you that religion and philosophy by themselves provides the means for division (sin) and delusion (mental illness). Do you know how to cross-reference religion with philosophy? On my website I'm explaining the connection between the God of Religion and the God of Philosophy. I'm claiming to be the god (religiously speaking) of the philosophy of aesthetics. The one who has been anointed above his fellow (fine) artists and scientists. It's an interesting angle (angel), that I thought I'd pass along to you.

More than any other type of entitlement whether it be land or the thought that one perspective is more "true" than another.Men have fought wars to their own means. We must answer the question. Which is best for a civilized Society?
Emperical knowledge through scientific testing is an extreme need for growth but is it best to disallow an intelligent design type belief system and simply say that all spiritual knowlwedge is illusion? Cannot we construct a society which understands the need for both?
I tend to believe that all which we see before us has the fingerprints of an intellegent designer behind it. Forget all of the "Testing" part of life. To be sent to a hellish fire is only a way to keep a Society civilized. It seems to me that our free will only is involved in about twenty percent of what we are born into and encountered within this life. Choices do come but within that environment of which we have been born. As a play one character must be poor to define rich, one slow to define fast and ultimately one to experience life, to give life to that which is not in this life. The "Designer" must be defined by what He is not, here with us.
The computers of the day are based on 0 and 1. One cannot be absolute, and by that definition, it is no thing. A zero on the other hand is simply "undefined" except for the fact that it is different than one. Like a play we must assume our roles and make our "free will" choices toward the means of goodness.
Maybe next time you will be "God" so please get through this hard finite life for the Spiritual to exist as defined by you.
Thankful we are that this realm is finite and not the other way around.
It is a case of this and that. There is no room for a third realm of eternal damnation. It does not fit mathematically. This must be brought to the forfront. We must start to realize that there is another side defined by the very basics of this experience. Another "Fingerprint of the "Designer".
Why have millions of years of Dinosaurs without "conscious thought of them". Were they placed at the moment of our ability to understand our existence, "counscious thought"? I believe this to be so. Would we not now have the wings to fly and the gills to swim through the ontological sequence of evolution?