The three-fifths compromise that counted slaves toward slaveholding states' representation in Congress--a good example of setting aside differences in politics, says the president of Emory University, and one we should follow today!
A student in my African American lit. class told me that the chapter on the Civil War in her little sister's Virginia high school US history textbook is titled "The War of Northern Aggression."
I guess we don't study history to avoid making the same mistakes because . . . we didn't make any!