Against my argument that America was a Christian nation, or even a Protestant nation, or more specifically a Calvinist nation, is the argument that Rome was the model for America, and not Christianity. This claim is based, for example, on the presence of Greco-Roman architecture in the nation's capitol.
Unfortunately, there has long been a connection between churchmen and Rome. Those who admired Rome were not always as anti-Christian as they are alleged to be by those who say America is not a Christian nation.
I was unaware of this factoid until reading it at Salon.com, "The Pledge of Allegiance is un-American":
In 1954, Congress inserted the words "under God," following an influential sermon by a Protestant pastor who argued that the model for the United States in the Cold War should be ancient Sparta.
An amateur internet infidel might claim that America's Founders wanted America to be like Sparta, and therefore would not have wanted "under God" to be in the Pledge of Allegiance. Obviously a bogus argument.