In 1954, President Dwight D. Eisenhower's urged, the Congress legislated that “under God” be added, making the pledge read: 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.
Prior to 1954 the pledge read: I pledge allegiance to the flag of the United States of America and to the Republic for which it stands, one nation, indivisible, with liberty and justice for all.
The constitution states that there is a separation of church and state: "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof"
Clearly placing "Under God" in our national pledge, is showing respect, and superiority to 1 religion over the rest.