Notions of American exceptionalism have a gut-level appeal that perhaps help explain both the American zeal for things individualistic and biblical. Yet, notions of convergence, either induced by capitalism or industrialism, suggest that the U.S. should look similar to Europe. Both exceptionalism and convergence have taken their hits, not the least with the way they play with a kind of false homogeneity.
On the other hand talk about the persistence or dominance of religion in the U.S. is about something homogenous, or at least doesn't easily include those variants deployed against social injustice. Come to think of it, a rock-ribbed christian probably prefers a libertarian theology over a liberation one.