The Slate writer has five pieces of it.
First, he says that pro-lifers should “pursue a culture of life, not a legal regime.” Replace “not” with “and” and I’m sold. Seriously, Saletan doesn’t explain why pro-lifers should not (continue to) try both to change the law and to reduce the number of abortions within the existing legal regime. Second, he says that we should as a movement help pregnant women in difficult economic circumstances and support government policies that help them, too. The movement already does the first part of this to the extent it is able to. As for the second part, if there are programs that can provide such help without unintended negative consequences that outweigh the good they do, then those programs should indeed have our support.
Third, 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?
Fourth, he says that we should push for earlier rather than later abortion. No deal.
Fifth, he suggests we should (I paraphrase) join a coalition with him rather than with pro-lifers who disagree with him. The logical force of this counsel depends on the strength of the rest of his advice.