Saletan says that if pro-lifers "were to embrace contraception and give it moral sanction," it would reduce abortion more than any anti-abortion law. I'm highly skeptical. Are people really having sex without contraception because pro-lifers have refrained from proselytizing in favor of contraception?
The simple reason for this preference for more unwanted pregnancies by the pro-life movement is that the Protestant wing - which might gladly promote condoms - cannot offend the Catholic wing which does. Until the Vatican hierarchs come around, more abortions will take place - because they'd rather encourage what they regard as mass murder than reconsider their position on rubbers and pills.