I think its rather peculiar. It's not in keeping with our founding documents our founding vision. But I'd guess you'd have to ask the Obama administration why they purged all this language from their platform. There sure is a lot of mention of government so I guess I would put the onus on them to answer why they did all these purges of God.
We are biological creatures. We are born we live we die. There is no transcendent purpose to existence. At best we are creatures of reason and by using reason we can cure ourselves of emotional excess. Purged of both hope and fear we find courage in the face of helplessness insignificance and uncertainty.
I've purged myself of bitterness and anger and remained open to love.
For the progress of scientific knowledge will lead to a constant increase of expenditure.