If the Republicans did point out such things as building restrictions that make it hard for most blacks to afford housing, even in places where they once lived, they would have the Democrats at a complete disadvantage.
It would be impossible for the Democrats to deny the facts, not only in coastal California but in similar affluent strongholds of liberal Democrats around the country. Moreover, environmental zealots are such an important part of the Democrats' constituencies that Democratic politicians could not change their policies.
Although Republicans would have a strong case, none of that matters when they don't make the case in the first place. The same is true of the effects of minimum wage laws on the high rate of unemployment among black youths. Again, the facts are undeniable, and the Democrats cannot change their policy, because they are beholden to labor unions that advocate higher minimum wages.
Yet another area in which Democrats are boxed in politically is their making job protection for members of teachers' unions more important than improving education for students in the public schools. No one loses more from this policy than blacks, for many of whom education is their only chance for economic advancement.
But none of this matters so long as Republicans who want the black vote think they have to devise earmarked benefits for blacks, instead of explaining how Republicans' general principles, applied to all Americans, can do more for blacks than the Democrats' welfare state approach.