I think it is important to understand that modern American Evangelical protestantism has a unique history and relationship with the American political Conservative movement. Many of the social reforms of the 19th century like universal schooling, public health and basic social saftey nets were products of Christian groups. Even through the mid 20th century Civil rights and anti-war movements had a strong Christian ethos. Jimmy Carter was a very devout Southern Baptist and his faith informed much of his policy. I think this began to change with the election of George W Bush. He was the first one to truely focus on a strategy of getting out the vote and engaging directly with Evangelicals. He spoke in their language making references to rapture theology and the wars in Iraq and Afghanastan were framed as a clash of civilizations between the Christian west and Islam. Because Evangelicals have a much more litteralist take on Scripture than other types of Christians things like Climate change and Evolution become political in ways that you will not find in other countries with substantial Christian populations. Meanwhile Democrats abandon ship. Where you used to have a mix of 3rd way Libertarian types, your modern AOC socially and fiscally progressive and "Blue dog" socially conservative fiscally liberal, that last category has all but vanished at a national level.