Motor City Mayor Kwame Kilpatrick is right to be distancing himself from a City Council proposal to create a racially exclusive business district in Detroit to help black entrepreneurs. Not only would the plan, dubbed African Town, heighten racial tensions unnecessarily. It could also exacerbate the very problem it aims to solve. The insidious premise of this economic development plan, which was approved last week in a 7-to-2 vote overriding Mr. Kilpatrick's earlier veto, is that immigrants from Latin America, Asia and the Middle East are "stealing" jobs and resources from native blacks. But for the presence of these foreigners,...