Juan Cole gives an impassioned discussion of this speech and what it means in America, with the city of Detroit as an example. Well worth a read. Here’s the first paragraph:
Barack Obama was talking about something very personal to him, about being rooted in family and community. He recognizes that race had shaped both and had wounded both. He refuses to give up on the communities in which he is rooted even if they sometimes act out on issues of race. He cannot, he says, afford to give up, and neither can we. No matter what happens in electoral politics, on March 18, 2008, Barack Obama entered the American history books with his brilliant, searingly honest speech on race.