by Karl Zinsmeister

About the author: Karl Zinsmeister is editor in chief of the American Enterprise, a conservative journal of opinion.

Originally, notes family historian John Sommerville, marriage arose to create "security for the children to be expected from the union." Yet nowadays "the child's interest in the permanence of marriage is almost ignored." During the divorce boom that began in the mid-1960s, divorces affecting children went up even faster than divorces generally, and today most crack-ups involve kids. Since 1972, more than a million youngsters have been involved in a divorce each year.

The result is that at some time before reaching adulthood, around half of today's children will go through a marital rupture. Most of these youngsters will live in a single-parent home for at least five years. A small majority of those who experience a divorce eventually end up in...