Young parents Bristol Palin and Levi Johnston may have gotten engaged again recently, but they are still a quintessential "red" family trying to swim against the tide of family change, say two family law professors who have launched a debate about "red" and "blue" American families. The 2004 and 2008 elections showed a divided America — and that division extends even to families, Naomi Cahn and June Carbone write in their book, "Red Families v. Blue Families: Legal Polarization and the Creation of Culture." In blue states, families tend to be well-educated, have high-paying jobs, be tolerant of diversity and...