All the white people I know deplore racism. We feel helpless about racial injustice in society, and we don't know what to do about the racism we sense in our own groups and lives. Persons of other races avoid our groups when they accurately sense the racism we don't see (just as gays spot heterosexism in straight groups, and women see chauvinism among men). Few white people socialize or work politically with people of other races, even when our goals are the same. We don't want to be racist - so much of the time we go around trying not to be, by pretending we're not. Yet, white supremacy is basic in American social and economic history, and this racist heritage has been internalized by American white people of all classes. We have all absorbed white racism; pretence and mystification only compound the problem.
Another post on microagressions that deals with the challenges faced by "oppressors."
This post connects with a lot of Tim Wise's work on how racism harms white people. His book White Like Me does a great job spelling that out.