New York Mayor Michael Bloomberg is being lacerated for not including any clergy in the principal ceremony marking the 10th anniversary of 9/11. Nor will there be a prayer.

If a minister can deliver an invocation at a presidential inauguration, it's hard to see a constitutional argument against a non-denominational, clergy-led prayer at a city’s memorial event.

One of the arguments for clergy-led prayer is that it's innocuous -- a form of what legal scholars call "ceremonial deism."

But here's the catch: If various religions earnestly believe in propositions that are unique to them -- say, the saving power of Jesus' death for Christians -- a non-denominational prayer is a kind of betrayal.

Perhaps the argument against that sort of observance isn't legal but religious.

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--Michael McGough

Photo: Mayor Bloomberg. Credit: Jamie Rose / Getty Images