Did God send a new revelation in 1930 telling the Anglican bishops that this was all a mistake? Did someone discover that "be fruitful and multiply" meant something different from what all Christians thought it meant for the previous 1,900 years? Did we suddenly come to understand human sexuality better than our spiritual ancestors? Or, perhaps, did we pick up an idea from a culture that is increasingly hostile to fertility and chastity? Did we take a wrong turn?

One way to tell if you've taken a wrong turn is to look at the consequences of the turn. After all, if there is and ought to be, by God's design, an intrinsic link between sex and childbearing, then separating them would probably mess things up. And so it has.

Contraception separates sex from procreation, and also weakens the consequences of extra-marital sex. As a result, many scholars see the widespread acceptance of contraception as a logical and cultural precursor to both legal abortion and the demise of marriage. As Glenn Stanton and Bill Maier of Focus on the Family put it in Marriage on Trial (pp. 121-122): "[A] major redefinition of marriage occurred with the growth of our culture of contraception. The emergence of widespread contraception, especially the emergence of the pill, helped separate sexuality and marriage from childbearing."

In his encyclical Humanae Vitae, Pope Paul VI warned of the effects of cultural effects of contraception:

Responsible men can become more deeply convinced of the truth of the doctrine laid down by the Church on this issue if they reflect on the consequences of methods and plans for artificial birth control. Let them first consider how easily this course of action could open wide the way for marital infidelity and a general lowering of moral standards. Not much experience is needed to be fully aware of human weakness and to understand that human beings—and especially the young, who are so exposed to temptation—need incentives to keep the moral law, and it is an evil thing to make it easy for them to break that law. Another effect that gives cause for alarm is that a man who grows accustomed to the use of contraceptive methods may forget the reverence due to a woman, and, disregarding her physical and emotional equilibrium, reduce her to being a mere instrument for the satisfaction of his own desires, no longer considering her as his partner whom he should surround with care and affection.

Paul VI wrote those words in 1968, at the height of the sexual revolution and five years before the Roe v. Wade decision.

Of course, abortion and contraception are not the same thing. You could coherently oppose one and not the other. Moreover, it makes sense that abortion is a legislative priority but contraception, for the most part, is not. Abortion involves killing a human being. A simple ultrasound image is enough to expose its evil. Not so with most forms of contraception. Contraception severs the link between sex and conception, thus preventing a new human being from forming in the first place. Its moral problem is more subtle. It tends to reveal its character only at the end of a longer chain of inferences.

Catholics should be careful not to alienate their evangelical brothers and sisters in the pro-life movement—and vice versa. But just because abortion and contraception are different doesn't mean they are unrelated. All Christians should consider the possibility that we will never fully restore a culture of life until we have extracted ourselves from the culture of contraception.