I'm not so sure about your take on the 1st Amendment. It is for freedom of religion, not freedom from religion. It is just that there cannot be a national religion that is forced upon the populace.
I think it really was going for not forcing a religion no anyone...but, not that any religion could never be spoken about. The mere presence of a mention or investigation into religion is not forcing anything upon anyone else..it isn't like you won't pass a course if you don't convert.
I think there's been some miscommunication.
A common slogan on this topic is "freedom of religion implies freedom from religion". That's because "freedom from" means exactly what you're offering as an alternative--we are not legally required to have a religion and we are protected from religion being imposed against our will.