The best thing that could happen to the Democratic Party is for the Supreme Court to reverse Roe v. Wade. Liberal judicial activism in general - and Roe in particular - is the biggest gift the Republican Party has ever gotten. Because of Roe, three generations of Republican politicians have had the luxury of posturing about their opposition to legalized abortion, without ever having to pay the price for that opposition. If Roe is reversed, abortion will be outlawed in some states - although in fewer than either pro-life or pro-choice activists imagine. But an almost certain side effect of...