Amendment 1 of the U.S. Constitution: Congress shall make no law respecting an establishment of religion, or prohibiting the free excercise thereof...
In 1954, Congress added 'under God' to the Pledge of Allegiance, which, I feel, is an infringement to 'Congress shall make no law respecting an establishment of religion...,' and should be executed to protect the other people of a different belief (Ismalmic, Jewish, Atheistic beliefs, etc.).