Ironically, this is more or less the same issue as gun control and the 2nd amendment - call it - thought control. The 1st Amendment merely states that the government is NOT INVOLVED IN ANY WAY with religious issues - that the sector of life involved with faith is NOT to be in any way trammled by offical sanction. So it's bloody well irrelevant if people pray in school - what is NOT irrelevant is an offical act by the govt that directly attempts to sponsor specific icons, customs, and doctrines of this or that particular sect - as the idiot in Alabama is doing with his Mosaic monument.
This is why I cannot claim liberalism, in spite of agreeing with them on most issues - they are just as obsessed with thought and behavior control as the rightists.
(Edit: according to your viewpoint, we should burn or melt all the money that states "In God We Trust", or at least all that bearing Masonic symbols (Novus Ordo Seclorum and all that). The presence of these symbols in no way represents an endorsement of a sect, because their presence does not in any way restrict the individual from believing what he pleases.)