United States is suppose to be for people of many religions and views. But limiting the pledge only to one God is not right, notice the capital "G." United States is suppose to have separation of church and state.
In the Jewish religion God's name is Elohim, In Islam it is Allah, in Christianity it is God. What if you believe in multiple gods. Lets stop the separation and bring people together by altering the pledge to pre 1954 which went like this
"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."
So all people feel like they are part of United States, and that they should feel right to protect this country.