Thomas S. Kidd, on the tension that has always existed within evangelicalism between the “establishmentarian impulse” and the more activist and reformist (though less overtly political) drive:

Evangelicals have been most faithful to their tradition when protesting against manifest injustices like slavery rather than trying to impose a de facto or de jure establishment. Attempts to ban Sunday mail delivery, the sale of alcohol, and the teaching of evolution all reflected that establishmentarian impulse. This impulse has routinely taken evangelicals away from their dissenting roots. Well-meaning (or crassly opportunistic) politicians have often led rank-and-file evangelicals into such establishmentarian efforts. Some of those politicians (such as [William Jennings] Bryan) have been evangelicals, some not. But the establishmentarian crusade of the early 1920s culminated in Bryan’s sensational collapse at the 1925 Scopes “Monkey Trial.” Promoting anti-evolution laws was one of the most misguided evangelical ventures ever because it focused so much energy on mandating a particular Christian view of science in public schools. The Scopes Trial was a major precedent for the crisis of politicization that bedevils evangelical Christians today.