The words "under God" were added to the US Pledge of Allegiance in 1954, during the Cold War, under the Eisenhower administration, to mark a distinction between the USA and so-called 'godless' communism of the Soviet Union and the People's Republic of China.

When people today quote "one nation, under God" as evidence that the founders of this country created a Christian Nationalist country, they are repeating historical inaccuracies. You are welcome to correct them.

@VisualStuart If you want to read a great book on the development of Christian America as a concept Kevin Kruse's One Nation Under God is really interesting.

@SRLevine
This cultural history is also good. American Jesus: How the Son of God Became a National Icon.
https://www.librarything.com/work/9795113

@VisualStuart

American Jesus: How the Son of God Became a National Icon by Stephen Prothero

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@SRLevine @VisualStuart Don't call it "Christian" call it religious nationalism. The kind of Christianity practiced in the US would be repudiated by Christ Himself, it bears little resemblance to Christianity in the rest of the world.