I agree with most of what Ross says here, including his contention that abortion policy is properly under the jurisdiction of the states. The trouble is that there are a lot more pro-choice but anti-Roe writers and thinkers than politicians fitting that description in either party. The last Republican presidential candidate I trusted to be pro-choice and anti-Roe was Pete DuPont in 1988. On Roe, Rudy Giuliani was equivocal at best. Gary Johnson has been better, but I’m not sure many people would argue he is the Republicans’ best shot against Obama.
Judges may be a good reason to support a pro-choice Republican over a pro-choice Democrat. Judicial nominations are a less solid rationale for supporting a pro-choice Republican over pro-life alternatives in a GOP primary. Pro-lifers have had difficulty getting anti-Roe Supreme Court justices nominated and confirmed even under pro-life Republican presidents. Why expect that track record to improve under a pro-choice one?
If Roe did fall under a pro-choice Republican president, he or she would need to be Ross’ federalist variety of pro-choicer. Otherwise, we’d have a president who would sign something like the Freedom of Choice Act, and pro-lifers would be no better off.
Finally, there are a lot of pro-lifers of convenience in the Republican Party. Some, and perhaps many, of them would become pro-choice Republicans if the ceiling on their political ambitions was lifted by accepting pro-choice GOP presidential nominees. I acknowledge that this isn’t a persuasive argument to those who want to maximize GOP electoral viability on other issues, but it is a strong consideration for those who want to maximize pro-life influence.