"I pledge allegiance to the Flag of the United States of America, and to the Republic for which it stands, one Nation under God, indivisible, with liberty and justice for all."

For those who don't know: That phrase was never in there until 1954 when it was added - a McCarthy effect- under President Eisenhower. Many have tried to have it removed since.

Not exactly a new addition then.
Pledge - composed 1892
Adopted - 1942
Unchanged since - 1954

So mention of God has been it it for 48% of its existance, and has been part of it for 82% of the time since its adoption by Congress.

Hardly a new change then.