I can't comment on the American Constitution as a Brit, because I've never studied it ... I only really know those first beautiful words of the Declaration of Independence. So I'm just contrasting and comparing my impressions about the UK and the USA in the present day.
Its true that in the UK we do still have the Church and State tangled up ... the Queen is Head of State still, and she's also still the Head of the Church (I forget what the title is, but in there somewhere is "Defender of the Faith", originally granted by the Pope to Henry VIII, which is quite funny considering what came a short time later).
Anyway ... yep, although we have that tangle still, we're a much more secular society, in general, than America. I literally don't know anyone, any friend or relation, who goes to church. No one, and I think thats maybe quite uncommon in America. To me, all religions are artificial, *man* made (not *woman* made) constructs, no more, no less. I think all of them, in some way, reflect the deeper spiritual truths, but they're usually affected by the society and the time that expresses them.
I think there are one or two schools in this country that teach creationism, but its certainly got no place on the curriculum, and very, very few people take it seriously.
The major thing that sticks in my mind about religion and public life in the two countries, is the way American politicians, or the ones we hear about in the UK anyway, refer to God and God's strength and God's guidance, pretty regularly. When Tony Blair was coming to the end of his time in office, he did it once, he said that God would judge what he'd done in relation to the Second Gulf War. And the uproar was immediate, it was basically this: no, Tony, you'll be judged well before that. The voters will judge you. He resigned, of course, before we could, but no one over here has any doubt about the level of public disapproval of statements like that.
