From the book 'Complicity's introduction is something that sort of makes the same case I was making earlier in this thread. It's the biggest peeve of mine about learning any history, not just American.
"The history of the United States is typically told backwards, as a means of explaining to members of the current generation how their country grew to be the way it is. In such an account, slavery is a single chapter, a background event limited to one region of the country and overwhelmed by the more recent events of pioneers moving west, railroads spanning the continent, and great cities growing up around stockyards and steel mills.
A history told frontwards, however, pushes slavery into the foreground, inserting it into nearly every chapter."