But don't young marriages tend to end in divorce? If we communicate to young people that we think they're inherently incompetent that will become a self-fulfilling prophecy, but it was not always the case. In fact, in the days when people married younger, divorce was much rarer. During the last half of the 20th century, as brides' age rose from 20 to 25, the divorce rate doubled. The trend toward older, and presumptively more mature, couples didn't result in stronger marriages. Marital durability has more to do with the expectations and support of surrounding society than with the partners' age.
A pattern of late marriage may actually increase the rate of divorce. During that initial decade of physical adulthood, young people may not be getting married, but they're still falling in love. They fall in love, and break up, and undergo terrible pain, but find that with time they get over it. They may do this many times. Gradually, they get used to it; they learn that they can give their hearts away, and take them back again; they learn to shield their hearts from access in the first place. They learn to approach a relationship with the goal of getting what they want, and keep their bags packed by the door. By the time they marry they may have had many opportunities to learn how to walk away from a promise. They've been training for divorce.
http://www.nationalreview.com/comment/comment-mathewes-green092002.asp