I don’t think [the founding fathers] made any mistakes given the society they had to work with at the time. However, I really don’t think they understood that religions other than Christianity, given sufficient numbers of adherents, could pose an existential threat to the form of government they created, which was built for the Christian civilization they lived in, however many sects there were at the time. For example, the concept of separation of church and state is a strong feature of Christianity, but totally absent – even abhorrent – in Islam.

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The Spaniards, given their experience, would have thought the idea of total freedom of religion a form of insanity. And, as we see today, “secular” ideologies such as equalism, which may have derived in part from Christianity, have little use for the concept of freedom of religion (or any other freedoms).