Kweisi Mfume recently announced his departure as NAACP President, and not a moment too soon. His tenure has been a disaster for the storied civil rights organization, driving it deeper into liberal irrelevance. But that doesn't mean it still shouldn't be defended against the current IRS probe of its tax-exempt status. Back in October the NAACP was informed that it may have violated a law that prohibits charities, churches and other nonprofits from engaging in partisan activities. Under Mr. Mfume and chairman Julian Bond, the group has accused President Bush of being at war with black America; compared Republicans to...