The Founding Fathers were concerned with protecting church autonomy from the state. The revisionist Constitution the Left touts reads a little differently. They proceed on the assumption faith ought to be excluded from the public square, in toto. The founders felt that all faiths should have access to the public square - equally. It's a subtle, but profound difference, but it is read this way by the Left as a way of sterilizing public debate from any "infection" of faith.