THE DEMOCRATIC National Committee won't officially elect its next chairman until Feb. 12, so Howard Dean doesn't have the job wrapped up just yet. But the Association of State Democratic Chairs endorsed him this week, and two of the five other candidates for the position have since dropped out. Clearly, the Democratic chairmanship is now Dean's to lose. And that should have reasonable Democrats worried, because their party's ills aren't going to get better with the medicine Dr. Dean is prescribing. As governor of Vermont, Dean was regarded as a budget-balancing, gun-owner-friendly centrist. As a candidate for president, he turned...