It is SUPPOSED to be secular, according to the founding principles and the constitution. But the religious majority are working hard to keep it under Christian control.

“The government of the United States is not, in any sense, founded on the Christian religion.”
— John Adams

Are you referring to the Pledge of Allegiance? If so, the "under God" part was added during the 50s by the lobby of the Nights of Columbus. Is not part of the original and I never say these two words when reciting the POA

Sorta depends on who you’re talking to, doesn’t it? Religious nuts will always say our country was founded on religious principles, while others say it was founded on freedom of religion principles, while there are also those who say it was founded on freedom from religion principles. What do YOU say?