We never used to claim America was a Christian nation
It’s short but sweet: in 1797 the Senate ratified the Treaty of Peace and Friendship with the Barbary States (today’s Tunisia, Algeria, and Morocco, and what was called Tripolitania). These were autonomous provinces of the Ottoman Empire in North Africa that made a living harassing shipping in the Mediterranean. Barbary pirates were a scourge to Ottoman, European, and U.S. shipping, and the U.S. attempted to use diplomacy to protect its shipping (though the U.S. would eventually fight two wars with the Barbary States in 1801 and 1815 to put a stop to pirate attacks).
Article 11 of the treaty reads thus:
As the government of the United States of America is not in any sense founded on the Christian Religion,-as it has in itself no character of enmity against the laws, religion or tranquility of Musselmen,-and as the said States never have entered into any war or act of hostility against any Mehomitan nation, it is declared by the parties that no pretext arising from religious opinions shall ever produce an interruption of the harmony existing between the two countries
Let’s break that down: 1) the U.S. is not founded on Christian principles; 2) the U.S. would not sign a treaty with any state that had “entered into any war or act of hostility” against a Muslim nation; 3) religious difference can never be used as an excuse for war between the U.S. and the Barbary States.
We offer this not to the ongoing debate about accepting Muslim refugees from the wars in the Middle East, nor to say there is no difference between Islam as practiced in 1797 in North Africa and Islam as practiced today in nations the U.S. is in conflict with. We offer it as rebuttal, from the Senate itself, of the poisonous idea that the U.S. was founded to be a Christian nation with a religious mission. Read any founding text and you will fail to find that belief proffered in any way. The mission of the U.S. is to promote representative democracy, liberty and justice for all, and that’s it.