Maybe you should read some history. In the Treaty between the United States and the Barbary pirates, unanimously ratified by the United States Senate in 1797, we declared as follows:
"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."
Jesus Christ is mentioned in the text of the US Constitution, where he is referred to as "Our Lord."