The City upon a Hill
This needs a little history so let me explain.
In 1630, John Winthrop, head of the Massachusetts Bay Colony, would make a speech incorporating a sentiment from Matthew 5:14, “You are the light of the world. A city that is set on a hill cannot be hid.” This sentiment captures the spirit of American exceptionalism, that its citizens had something special to say and teach the world. A rejection of the hidebound old Europe, these new Israelites had been gifted with a Promised Land, empowered to expel its inhabitants, and destined for earthly success as long as they honoured God's law. And their constant record of early success was proof that God was on thier side.
Despite the arraogance, this wasn't all bad. No nation can stand the scrutiny of history, and their reord includes great moments like the Marshall Plan. They embraced individual freedom and the can-do spirit, and with it democracy, free enterprise and a penchant for good works. They were a light to the world in their way. And this belief has lasted. Reagan would base his presidency on it. And it worked. He tore down the evil Soviet empire.
There is of course much more nuance to American history,and much more self-interest, but don't underestimate its value, or its importance in American Christianity.
And understand that also is exceptional in its own way. The other great religions (Islam, Buddhism, Taoism, etc.) remain attached their roots. Christianity however knows no geography. Beginning in the Middle East, its next centre would be Europe, then to the Americas, and more recently to China. The current focus of Christianity is in the Southern Hemisphere. It has always been fluid, but as its wave passed over the United States, it also joined with that culture.
Not every part of course. The New England Puritans were overrun by the more flexible Baptists and Methodists from further south. The (German) Lutherans and the (Irish and Italian) Catholics always remained a side show. The heresies of 1830's upstate New York (Mormons, Later Day Saints, Milleniallists, Spritualists, etc.) would tend to go their own way. The Second Awakening of the 1840's was mostly political (Emancipation, Suffrage, Prohibition) with white women learning to use the church as their platform outside the home, determined to get their menfolk out of the bars. Even without the Civil War, the protestant of the southlands would need to double down, and then came Darwin.
Step back for a moment and recognize a Conservative will espouse a political philosophy that values tradition and social stability, preferring only gradual development, and then only if necessary. The Progressives in America would deal with evolution by deconstructing the Scriptures, denying the Bible's (the Word of God's) inherency and thereby leaving conservatives without any anchor. Their reaction was to enshrine Protestant faith into Fundamentalism, elevating belief in Scripture to the inflexible. May I now put the pieces together?
American fundamental Christianity has over time and become intimately associated with American exceptionalism, resulting in a conviction that both Scripture and America knows best. Moreover, if I were to guess, I suspect that American exceptionalism as an ill-defined belief now outranks Scripture, but both are under attack.
There is China. Global warming. Covid. School prayer. Abortion. Crime. Vietnam. Toyota. Islam. Social Media. Wherever they look, the wheels are coming off. That explains why they feel defensive but if you want these people to change without drama, you might want to learn a little history instead of just poking the bear.