Since the 70s I have found that the public discussion is only occasionally about abortion itself and the issues underlying it. It is a proxy for full cultural attitudes, usually in the form of accusation that the other side does not respect women, or the other other side does not value parenting, or is selfish. People say amazing things about each other. One interesting consistent bit came up at Althouse this morning (she is pro-choice and has taught law courses about the specific cases and the underlying legal [though it doesn't sound like philosophical - I could be wrong there] issues). We fought for this right. We fought to keep it. Such things make people invested in an issue, yes, but it is not of any use in telling us whether they were right or wrong. People fight for many things. Yet our heart does follow our treasure, especially if that treasure was time and self-definition. (Matt 6:21) The treasure-heart exchange flows both ways, but we usually only credit that we have given our treasure to something because our heart led us to. I think the other way is stronger. Her heart will always go to where her treasure has gone before. The sunk-cost fallacy applies also to ideas.
Abortion rights have been regarded as conquered territory by feminists since Roe, and any loss is considered an invasion over the Real Boundary, and a type of theft. The attempt by conservatives, and especially libertarians, to switch the ground of the discussion back to decisions by the individual states has not changed that. I think it is regarded as a ruse. Conservatives otherwise consider Roe to be the farthest expression of justices inserting their personal opinions rather than forcing themselves to stick to the text. Emanuations from the penumbra, indeed! We say Harumph! to that.
There is some pressure on becoming an evangelical to pick up a pro-life belief as something expected to be part of the club. I think this is less pronounced in those who grew up in the older evangelical denominations, such as the one I am in now. I don't know if it is also true for Catholics, though I suspect there would be at least some pressure, as they are noted for especially holding this position. It may not be mentioned all that often except to announce events one might attend or references to pray for the end of it.
Even though not all my classmates were pro-choice at William and Mary, I think there was a cultural pressure to regard that as modern, the choice of the smarter and career-oriented women - and the men who wanted to have any chance at them. It was part of a package of learning to leave the false and outmoded beliefs of your parents and childhood behind. It was expected in order to be part of the club. Some clubs, anyway, though unofficial. It still has that feeling to many women of my generation, at least. To be against abortion rights is to be nearly against women voting, or to be tolerating rape, or something. There is huge emotional attachment.
Related, because it is about the Althouse blog and debate in general, was her offhand statement last week that her comment section became conservative over time and is now mostly so, even though she is left-libertarian. She did not offer an opinion as to how this occurred, at least not there. She may have addressed it at another time. Do liberals not endure criticism of their views as well? Did the conservatives treat opponents more rudely and harshly? A few other possibilities occur to me as well, but I don't know a thing. It is something I have wondered about previously, that so many people who have only partial agreement with her feel so comfortable on her site. It's a mark in her favor, I think.