I think a good argument can be made that even if Obama himself was not a strong believing Christian--even if he were an agnostic--he would not ask to have "so help me God" dropped from the inaugural oath.

After the model, perhaps, of Henri IV ("Paris vaut bien une messe"). It's a simple question of picking your battles. There are far more believing Christians in the US who would notice the lack of "so help me God"-- (ably assisted, no doubt, by the media) --than the number of rabid atheists pushing for deleting that phrase.   And he needs the support of the first group on any number of issues--so there is no point in needlessly rousing even some of them against him.   The second group is very small--and their clout is even smaller.

As has been said, facts are stubborn things.

And I am by no means a strong Christian--just somebody who recognizes reality.