WASHINGTON — By all indications, the reluctant support by white evangelicals for Donald Trump against Hillary Clinton in 2016 has solidified into something like devotion.

In his analysis of the 2018 midterm-election results, political journalist Ron Brownstein found many groups plagued by second thoughts about their support of Trump. But not evangelicals, who display a "hardening loyalty" toward Trump's GOP. Evangelical support for key Trump policy priorities such as the border wall has jumped. When asked recently if there was anything — anything at all — that Trump could do to forfeit evangelical allegiance, Jerry Falwell Jr. replied: "No."

In an era of strange political alliances and events, this one remains notable. Headed into a possible impeachment battle, the most ethically challenged president of modern times — prone to cruelty, bigotry, vanity, adultery and serial deception — is depending on religiously conservative voters for his political survival. And, so far, it is not a bad bet.

Trump has understood something about evangelicals that many are unable to articulate themselves. White, theologically conservative Protestants were once — not that long ago — a culturally predominant force. Many of their convictions — on matters from sexuality to public religiosity — were also the default settings of the broader society. But that changed in a series of cultural tidal waves — the Darwinist account of human origins, the application of higher criticism to the text of the Bible, the sexual revolution — which swept away old certainties.

When conservative Christianity became re-politicized in the 1970s and 80s, the secular world — the world of federal judges, public schools, major universities and liberal politicians — was viewed as an aggressive threat to Christian ideals, institutions and identity. Over time, that struggle has taken on apocalyptic proportions in the minds of many believers. For some, it is nothing less than the end-times conflict of good and evil, which somehow culminated in fights against the Obama administration.

In this struggle, many evangelicals believe they have found a champion in Donald Trump. He is the enemy of their enemies. He is willing to use the hard-ball tactics of the secular world to defend their sacred interests. In their battle with the Philistines, evangelicals have essentially hired their own Goliath — brutal, pagan, but on their side.

It doesn't take much biblical research to discover that this isn't quite how God accomplished things in the original story. He actually employed a scrawny Jewish boy, using unconventional tactics, in order to demonstrate that His favor mattered more than worldly measures of strength. From a purely political perspective, however, the hiring of a Goliath is what interest groups generally do.

In this case, there is also a predictable political cost. The employment of an unethical, racist, anti-immigrant, misogynist Giant is not likely to play well with women, minorities and young people, who are likely to equate conservative religion with prejudice for decades to come.

Even in a distorted form, it contained the seed of a revolution.

This is true enough. But it is, fortunately, not the end of the story. At least it has not been the end in similar cases before. During the 19th and 20th centuries (and before) conservative religion was often used to justify slavery and segregation. Pastors and theologians blessed white superiority and urged African-American acceptance of the existing social order.

The Christian faith, however, was something more and different than its most visible defenders made it out to be. Even in a distorted form, it contained the seed of a revolution. After his Christian conversion during the Second Great Awakening, Frederick Douglass said, "I love the pure, peaceable, and impartial Christianity of Christ: I therefore hate the corrupt, slaveholding, women-whipping, cradle-plundering, partial and hypocritical Christianity of this land." Douglass was driven by Christian principle to challenge the Christian practice of his time.

Over the centuries, Christian faith (like other faiths) has been used to justify exploitation, oppression, imperialism and the persecution of minorities. But as its true precepts have taken root in reformers, Christian faith has also been a powerful source of criticism of those practices. And for a simple reason. Christianity inevitably raises the question: What if everyone we favor, and everyone we fear, and everyone we help, and everyone we exploit, and everyone we love, and everyone we hate, were the reflected image of God — unique, valuable and destined for eternity?

This Christian vision of human rights and dignity has grabbed men and women by the collar in every generation — the William Wilberforces and Dorothy Days and Martin Luther Kings. A hypocrisy becomes unsustainable. A seed gets planted. And a greater power emerges — revealing new leaders, and shaming those who reduce Christianity to a sad and sordid game of thrones.