The oddest of oddities is how "orthodox" Christianity, as it developed over the centuries, could be turned on its head at the Reformation, and how the Reformation itself could be turned on its head by evangelical Christianity. It is not surprising how different "orthodox" Christianity is from evangelical Christianity. In many salient ways, the heresy of heresy is itself anti-Christian. What is marketed as "evangelical Christianity" bears little resemblance to historical Christianity, and in many ways is diametrically opposite.

It's bad enough that "orthodox" or historical Christianity was (and still is) pernicious, but this "new" species of religion that uses some of the original language and tools bears no resemblance to the original. In many senses, it is too Jewish to be Christian. The dominance of special dispensation, divine election, God's chosen, using Jewish tribal laws (which for Jews was meant only for other Jews, not to be imposed outside the tribe), has morphed into a zealotry to restore the pre-Messianic state to prepare for the Second-coming of the Messiah. Nevermind its utter incoherence, it does what you describe: It empowers the powerless to rule.

Initially, I assumed it was a great marketing effort to make money (which it is), and what better way to do that than to insist it comes from God. Okay, that purchases consumers, but why have the consumers become militant ideologues as soldiers in a culture war to subvert the ordinary, common-sense view of the world. Why are they so bent on upending the liberal tradition on which this country was founded, then make the preposterous claim that it was founded on Christian principles (it was not), and that it must be a Christian nation in order for salvation and Armaggedom to occur? Why the overt hostility to benign science?

The similarities to Marxism cannot be discounted. The ideology becomes so paramount, so self-reinforcing, so uniting, that the "struggle" is itself the raison d'etre, the ideology the tool. Good must conquer evil, not a bad idea actually, except that evangelical Christianity's idea of "good" and "evil" is itself evil, and the way to achieve its evil is more evil. That it has taken place in America of all places, which just ended a Cold War to avoid totalitarianism, only to be followed by a new authortarian scheme, where the homosexual has replaced the communist, where biblical morals (not even Jesus's morals) are the cause celebre is utterly fascinating as it is scary. Returning to Marx for entirely speculative purposes, is there something about Modernity that has caused this abberrant phenomenon to occur? Is it akin to capitalism giving rise to the proletariat? The weak triumphing over their lords? Is the anxiety over modernity too intolerable to face without imposing this "template" over it to give it some sense? I really have no clue.

Whatever gave rise to this phenomenon, it remains pernicious and freightening. And worse, it continues to grow, increasing its threat to the modern liberal state and the entire Englightenment. Maybe Rollo May's diagnosis of social anxiety is the root, but the cancer itself is obvious to all but the infected.

the pulpit has never been a place where people go to have their beliefs challenged

(Italics mine). I think that sometimes people listen to sermons to have their beliefs challenged. Indeed a standard sermon form is to lambast the worldliness and hypocrisy of the congregation, sometimes with distasteful messages about hell thrown in.

On the wider point, I think you should rejoice at this: when religion gets into politics the long-term result is almost always harmful to that religion...