Indeed, one recurring problem is that we are who we are and not who we want to be. It's easier to get Our Hypothetical Racist Grandparents to agree that the premises of racism are wrong but it will be harder to get them not to be upset by at the thought of their granddaughter marrying one, even if they know they shouldn't be and actually do want to change.

Maybe someday we'll invent brainwashing that works?