Leave it to rebel Howard Zinn to put the 4th of July in its proper context:
On this July 4, we would do well to renounce nationalism and all its symbols: its flags, its pledges of allegiance, its anthems, its insistence in song that God must single out America to be blessed.
...in a nation like ours -- huge, possessing thousands of weapons of mass destruction -- what might have been harmless pride becomes an arrogant nationalism dangerous to others and to ourselves.
So, you know, put those flags away before you hurt someone. Rather, do humanity a favor and spend the 4th of July kneeling on a broomstick, begging forgiveness for the Mexican War. It's the least you can do as a willing dupe for the government's lies.