You're probably right that I should head back to Weber, but if I recall correctly, Weber's focus is more on what we would now consider white bread, mainstream protestantism (e.g. Scottish Presbyterianism).
Perhaps I am just ignorant about the history of religious movements in the U.S. but I am under the impression that this new Christofascism a lot different from old-fashioned, puritanical, idle-hands-are-the-devil's-plaything protestantism in that it desires to seize and wield political power and preserve U.S. hegemony. Does Weber discuss the brand of religion that appears in "Jesus Camp," for example? And how does Weber explain the surge in Jihadism?
-WD