The Supreme Court is going to hear arguments for and against displaying the Ten Commandments on government property. Rod Smolla at Slate rounds up the major issues involved, and summarizes what sounds to me like the most forceful argument in favor of displaying the Ten Commandments:

The cultural push to defend the Ten Commandments has … lots to do with the larger perceived value of the Ten Commandments as artifacts of history and culture—expressions of elemental moral precepts that inform our law and build our sense of shared values and community.

Fair enough, but here's a question: what on earth do the Ten Commandments have to do with law and government, especially American law and government? Look at the actual commandments in question:

1. "Thou shall not worship any other god but me." This certainly isn't a law, in the sense of being a constitutional principle or an enacted legislation, in the United States, or anywhere in the world, even Iran or Saudi Arabia. (Though some nations come close.) Leave aside the fact that, practically speaking, this could never be an enforceable law, and just note that the United States was founded specifically to break this law.

2. "Thou shall not make graven images." Again, not a law, not a government precept, and never will be. Does anyone, evangelical or otherwise, want to get into the practice of making Baal statues punishable in any way?

3. "Thou shall not take the name of God in vain." Again, the Constitution is set up specifically to break this law.

4. "Thou shall not break the Sabbath." Not a law, never will be. Now maybe this commandment builds our sense of shared values and community—kicking back and watching Sunday football is a pretty American pastime. But I don't think anyone wants to make the argument that Americans who work on Sunday somehow don't share "our values".

5. "Thou shall not dishonor your parents." Certainly not a law in any meaningful sense. Also note that this commandment is less a part of American values and community than it is in many non-Judeo-Christian counties—China, for instance. Youth rebellion seems to play a far bigger role in the United States than almost anywhere else.

6. "Thou shall not murder." Now this is a law! But it's also a law that's found in almost every single country on the face of the earth, Christian or otherwise. Odds are, it was a law or firm moral precept long before Moses ever came down from the mountain.

7. "Thou shall not commit adultery." Ah, here we go. Technically, we could make this a law, although it's none too likely. And I suppose we used to back in the day. More on this below.

8. "Thou shall not steal." See #6. Confucians, Muslims, Buddhists, atheists, pagan Greeks all frown upon theft. This doesn't much depend on the Ten Commandments.

9. "Thou shall not bear false witness." Another universal law. Not at all dependent on the Ten Commandments. It was the most important part of the Code of Hammurabi, in fact—and the Babylonians took perjury a lot more seriously.

10. "Thou shall not covet." I have no idea how you could make this a law. Besides, isn't coveting sort of the engine of good old-fashioned economic growth? I do believe our shared, free-market values actually depend on breaking the tenth commandment.

So what do we have? Four commandments (1, 2, 3, 10) directly contradict either the Constitution or American society. Three commandments (6, 8, 9) are certainly reflected in American law, but are not necessary for those laws to exist. Two commandments (4, 5) represent at best only fringe aspects of our culture, and certainly can't form as the basis for law. So that leaves number 7, the adultery issue. Very well. Let's ask those who wish to display the commandments whether they want to criminalize adultery or not. And if not, what relevance do the commandments have at all for American law, values, or community?