Moralizing is fairly effective if someone already classifies you as part of the in-group. That's how social stigma works, and generally how racism was broken in

Moralizing is fairly effective if someone already classifies you as part of the in-group. That's how social stigma works, and generally how racism was broken in the US. With the advent of TV, many people could see the effects of racism first-hand and could no longer justify it to themselves. Their disapproval was fairly effective at getting the more hardline members of their community to moderate their actions. In Virginia for example, traveling Klan members found themselves suddenly unwelcome in small towns, since either (a) cyncially no small town wanted to be the next one on the news as a lynching ground, or (b) small towners were legitimately disgusted by the seeing children beaten up for no other reason than their skin colour.