The decline of institutional Christianity over the last 40 or 50 years has empowered a side of American religion that has always been there. The sort of do-it-yourself, "create your own Jesus" kind of faith. But, the forms that faith takes do have a real reason they are so appealing.

What replaces Christianity isn't going to be Richard Dawkins, Christopher Hitchens, and so on. It's going to be something else and something secular people may not like very much.

Institutional Christianity has had clear secular benefits to American life for hundreds of years. It's played both a prophetic role in terms of generating moral critiques of American excesses, and so on, and also a communal role, in terms of building community as the country moved westward to the role my own Catholic Church played in assimilating generations of immigrants.

In many ways, American evangelicalism is somewhat stronger today than it was in, say 1955 - certainly more mainstream and influential in the culture as a whole. But, the increased strength of evangelicalism hasn't increased fast enough to compensate for the total collapse of mainline Protestantism and the pretty steady weakening of my own Roman Catholic Church.

I think it is very clear that, though great difference remained, evangelicals moved closer to Catholics, mainline Protestants and evangelical Protestants moved closer together, and this convergence coincided with greater institutional strength for all the Christian churches than, for the most part, you see today.

I read a lot of G.K. Chesterton. It was a fairly conventional intellectual path to the Catholic church, I would say.

I do think you can see, throughout American history, this temptation, and it's both a liberal and a conservative temptation, to take a healthy patriotism a little too far. For liberals the temptation is to say the purpose of politics is to straightforwardly bring the kingdom of God to Earth. For conservatives, I talk about Glenn Beck, the temptation is more apocalyptic and messianic, it's the temptation to say we did have a covenant with God, a literal covenant beginning with the Founding, and we are, like Israel in the Old Testament, falling away from it.