Independence Day! 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.

Here's a great quote from JFK's innagural speech:

"Let every nation know, whether it wishes us well or ill, that we shall pay any price, bear any burden,
meet any hardship, support any friend, oppose any foe to assure the survival and the success of liberty."