Let's get something straight. America has never been a "Christian nation." Those who believe otherwise have an obligation to say what part of our history was uniquely Christian. Was it when slavery was legal? How about when women were denied the vote? The Gilded Age? The Roaring '20s?

America is a nation in which Christians -- and every other religious and nonreligious person -- have the right to practice their beliefs in private and public free of government intrusion, except in some cases of life-threatening medical conditions in which the courts have occasionally intruded. It may make some evangelicals feel better to believe the country once reflected biblical principles, but despite generic quotations about "Divine Providence" that hark back to our founding, that's difficult to prove.

In the case of Kim Davis, the Kentucky clerk jailed last week for refusing to issue a marriage license to a same-sex couple, this flawed notion of a once pristine nation that reflected "biblical values" is again being tested, because we never seem to learn from the past. Davis has since been released by the same judge who jailed her with the caveat that she not interfere with her deputies as they issue marriage licenses to same-sex couples.

The late Charles Colson wrote a book titled "Kingdoms in Conflict." It was about what evangelicals call the Kingdom of God vs. the kingdom of this world. For most evangelicals, it appears, these kingdoms are headed in opposite directions toward different destinations. Attempts by conservative Christians to impose through politics and government the principles inherent in their kingdom have mostly failed. The reason is set out in their Scripture: "The natural person does not accept the things of the Spirit of God, for they are folly to him, and he is not able to understand them because they are spiritually discerned." (1 Corinthians 2:14)

If you are part of God's Kingdom, which has sought in nearly every generation to impose itself on the other, answer these questions: If you are pro-life, have you ever tried to get a pro-choice, non-Christian to accept your position? If you believe in traditional marriage and practice it, does your example and argument that marriage should be reserved for "one man and one woman" persuade proponents of same-sex marriage?

I didn't think so. That leaves members of God's Kingdom with two options: Force their views on those who don't share them (which an objective observer might say failed during the Moral Majority and Christian Coalition days of the 1980s and the Prohibition era before that), or accept the biblical verdict for that other kingdom: "And this world is fading away, along with everything that people crave. But anyone who does what pleases God will live forever." (1 John 2:17 NLT)

And what, you might ask, pleases God the most? It is the sharing of His salvation message with members of that other kingdom, which has the additional benefit for those who accept it of changing their outlook on some of those very things most Christians believe. In other words, changed hearts are usually followed by changed minds.

Kim Davis chose the wrong issue for her "martyrdom." Amazingbible.org lists more than 600 sins mentioned in the Bible, including adultery, fornication, divorce and lying. If Davis wants to be consistent she would refuse a marriage license for anyone who has sinned, which would limit the number of applications to zero since "all have sinned and fallen short of the glory of God." (Romans 3:23)

Davis had four options: Issue the license, have someone else issue it, resign, or go to jail. She chose to go to jail, which, unlike Rosa Parks to whom she is being compared, makes her look more like a religious fanatic than a martyr. Removal of her name from the marriage licenses would be a good compromise.

Uncompromising evangelicals should not expect more from a kingdom they regard as heading in another direction.

Cal Thomas is America's most widely syndicated op-ed columnist. He joined Fox News Channel in 1997 as a political contributor. His latest book is "What Works: Common Sense Solutions for a Stronger America" is available in bookstores now. Readers may email Cal Thomas at tcaeditors@tribune.com.