I really cannot believe I just read this entire thread. I really need to get a life.
Not trying to resurrect, and my apologies for necromancy, but after all the argument here, I wonder what official result is, and whether or not the building is all Goddy.
Some good arguments here, some fair and some less so.
The only thing I have to add - a motto is a slogan, a tag-line: It is trying to sell you something. Companies change tag-lines all the time, but only very rarely do they change their mission statement.
"In God We Trust" is a slogan, not a mission statement.
It is all well and good to blithely say that no harm is done, and maybe none is, maybe we should all trust in God more.... all of that still ignores the fact brought up in the OP - it is obviously, categorically, shadelessly unconstitutional, and a pork-barrel to boot. I hope it did not happen.