I think we should really keep in mind the Intent of Founding Fathers to include under god in the pledge of Allegiance. Founding Fathers were really intelligent when they came up with those words. I think the reason behind it is that everyone follows the same rules and regulations and really make up the first 3 amendments.
Whether you believe in a creator or not, the founding fathers were trying to unify a newly developed civilization to a unified goal. Even if you dispute the existence of a higher power, the key purpose of religion is to give people guidelines on how to live a kind, just and moral life. The Pledge of Allegiance is an American tradition and should not be changed.