For its day, it was a radical document. It put authority not in the hands of God or His representatives on Earth, or in the hands of some divinely elected potentate, but in the hands of the people. It also ensured that the people--any old people--would always be allowed to carry weapons around. Both of these provisions were incredibly radical.
But now for some reason the conservatives love the gun thing and the liberals don't, while the opposite is true about the establishment of a state religion: (many of) the conservatives seem to want Christianity to be enshrined as the state religion, while the liberals want to keep religion out of government (and vice-versa).