Over the course of 30 years of marriage debating, some arguments have been essentially "retired." Few scholars now say contemporary increases in father absence are "nothing new and alarming." Early enthusiasm about the capacity of "social fathers" (or as David Blankenhorn once memorably called them, "nearby guys") to substitute for actual fathers has faded for two reasons: First, because so few children in single-mother families "enjoy close, involved relationships with 'social fathers.'" Second, because statistically speaking, "living with a step-parent or a cohabiting boyfriend is associated with higher risks of behavioral problems as well as physical or sexual abuse."
But perhaps the most persistent argument used to minimize social and scholarly concern about the consequences of family fragmentation is the "not necessarily" argument: The absence of marriage doesn't always, categorically, lead to bad outcomes for children, scholars say. Of course it doesn't. But as Glenn and Sylvester note, this style of argument is very rare in the social sciences. "In our examination of JMF articles, we found no examples of authors pointing out, for instance, that growing up in poverty does not inevitably result in poor child outcomes. Nor do scholars apparently feel obliged to emphasize that low levels of maternal education do not necessarily lead to educational difficulties."
It's hard to argue with Glenn and Sylvester's conclusion: "The restriction of the 'not necessarily' statements to conclusion about negative family structure effects suggests that some scholars feel a particular discomfort about reporting or accepting evidence for such effects."