Fundamentalist zealots are adamant in asserting that the United States has always been a Christian nation and should continue to be one.
In spite of a lot of historical evidence to the contrary, I would like to, for the sake of argument, grant the religious right their point and assert that, rather than Christianity making us a great nation and a great people, tolerant and peace loving, this horrid religion has framed some of our most egregious, totalitarian practices and policies. From the genocide of indigenous peoples, to slavery, anti-Semitism and the present day misogamy, Islamophobia, homophobia, anti-science, and our support of the criminal government of Israel, Christians are behind the worst of the worst this nation offers to the world as examples of our "democracy."
Lest I encourage a barrage of rebuttal from secular Christians, let me define a Christian here as anyone who can recite the superstitious absurdities of the Apostles' Creed with a straight face.
Under the banner of Christ The King, Christians have throughout our history been the leading voice for American exclusiveness which, to misquote the Good (sic) Book, gives America dominion over the whole world, its resources and the exploitation of the labor of lesser peoples. It blesses the rape of our world's natural resources, the destruction of our landbase and the extinction of precious species and indigenous peoples.
If this is what is required to call us a Christian nation then I would agree that the bad behavior that has been our trademark since the incursion of the white man on this continent has been encouraged and led by Christians.
Of course what these zealots are actually trying to achieve by insisting we return to "the Christian principles upon which this nation was founded" is in reality a call to theocracy that they hope will be more severe than the Iranian Muslim variant. Make no mistake, religion always puts on its best face in a secular society. As our founders, who remembered well the abuses of such fundamentalisms as divine right of rulers, and religious sanctioned iron-clad class structures, knew official state preference for a particular religion always breeds tyranny.
Jefferson wrote, "I have sworn upon the altar of God eternal hostility against every form of tyranny over the mind of man." By God he probably meant the non-personal, Deist God of Nature and by tyranny he most certainly meant Christianity.