Many whites - especially ones that have deep roots in this country, have no sense of their own history. So deep is their sense of entitlement as "Americans" (as white Americans), that the mythology of Great White reads like gospel truth: Whites aren't different - everyone else is. Its the reason "non-whites" are people of color (as opposed to the colorless ones: whites!)
In order for racism to change (to become unveiled, see the light), Euro-Americans must see the priviledge illustrated in our language, our sense of entitlement, our American history as invaders, conquerors, pioneers - everything.
Most whites really aren't up to that. Notice how defensive people get and start bitching about "politically correct" when this dialogue has been raised (a bitter, cynical term in my book). Couple this with the fact that America is "king of the world" - not a recipe for change.