This post from Scot McKnight's "Jesus Creed" blog is, I think, vitally-important reading for all Christians today: Beck's Black Robe Brigade (by John Fea).
John Fea, Professor of History at Messiah College in Pennsylvania, has written a helpful reflection on the intersection of American history (or some parts of it) with faith and politics. Fea's assertion, which I believe is true far too frequently, is that we are regularly being presented with claims and conclusions that are based on parts of history, and/or that are based on simple answers to questions that are far from simple (if they can even be answered at all).
The issues discussed in the aforementioned post are very real and present issues that are coming soon to a town near you (if not to a church you belong to!). It is worthwhile to be aware of all of the questions asked in that post, lest we fall into blind or ignorant acceptance of cultural/political half-truths.
This dovetails with ideas that I've been reflecting on, and intend on posting about, centering around the question, "Who are you quoting?" (Look for that in the next couple of weeks, hopefully.)
Fea has a forthcoming book, Was America Founded as a Christian Nation? A historical introduction which is due out in February (pre-orders are available through Amazon-- see the link for the book).