Whereas differences in ethnic background and religious practice and doctrine once determined the religious identity of Americans, it is now far more common for this identity to be determined by one's position on issues tied up with the culture war: abortion, euthanasia, the breakdown of order and authority in the family, the banning of school prayer other public expressions of piety, the rise of a popular culture saturated with sex and violence, and the push for homosexual rights. To oppose these trends automatically places oneself in the traditionalist bloc within a given church, while reacting to them with resignation, indifference, or enthusiasm aligns oneself with modernist elements in the same church.This is an interesting point, but I'm not sure it paints a full picture. For one thing it's not a new trend but a recapitulation of the Red State/Blue State divide created by reactionary forces within the Boomer Generation, the Religious Right, and the Republican Party. After all, it's not the "modernist elements" that are splintering off and creating their own denominations or attempting to rein in or oppose change. It also doesn't say much about those "modernist elements" who rather than reacting with resignation or indifference, simply walk away from the whole church paradigm altogether. Those are the people that quit for a life spent reading Dostoyevsky or Kierkegaard.
What you have left in a lot of these churches are the complacent and the crackpot which doesn't speak well for the spiritual lives of any of these denominations.
(What I'm really waiting for is this trend to show up in Sports. Then you'll really see something. In Scotland, for example, the football clubs in each of the major cities are divided between Catholic and Protestant, and so your background determines which team you were for. Now imagine if that were true of Yankee fans and Mets fans. Or imagine if there was a schism between conservative Red Sox fans and liberal Red Sox fans. I'm a Buckeye fan, but there's also a lot of conservative red neck types that support OSU -- what am I supposed to do? Cheer for Michigan?)
