My advice, usually unheeded, to anti-choicers: Don't invite people to ponder the question of whether or not the world would be a better place if you had never been born. They may, upon thinking about it, come to a conclusion you don't like. Of course, most people are too polite to say, "Now that I think about, the world would probably be just fine without another shrill misogynist sex-phobe," and anti-choicers playing the "what if MY mother had an abortion" card are simply exploiting said politeness. But because people don't say something out loud doesn't mean they're not thinking it, so the "what if I had never been born?" argument may not be as much of a slam dunk as anti-choicers like to think it is.
Case in point: the "Conceived in Rape" tour of people such as anti-choice activist Rebecca Kiesling claiming that they are only here because the state forced their mothers to give birth to a rapist's child. They intend to use their existence on the planet as evidence that it's just awesome for the state to force women who have been raped to give birth against their will, which strongly violates my No. 1 rule of not inviting people to ponder how much of a value-add you really are for the world. For a movement that is defined by logical errors, the anti-choice reliance on the "what if" question when it comes to abortion may be its biggest logical error. Sure, the pregnancy you're aborting could result in the next Beethoven if you had the baby. But it could also produce the next Hitler. I'm not a big fan of the "what if" for that reason.
Plus, the "what if" question applies to far more than abortion. For instance, there are all the births that are prevented by not getting pregnant in the first place. Sure, anti-choicers address that question by being hostile to contraception, as well, but they never take that one to its logical conclusion by also opposing abstinence. The number of children we don't have is functionally infinite, but we're not doing the what-if babies any favors by electing to spend some evenings watching TV instead of getting knocked up over and over again.
This problem for the "what if" question is particularly stark when you're talking about rape. Sure, the conceived-in-rape people wouldn't be here if abortion hadn't been banned when they were conceived. But they also wouldn't be here if their fathers weren't generously willing to rape. They needed both the ban on abortion and the rape to exist. So, by their own logic, rape is a social good. Perhaps when we're banning abortion to make sure people like Kiesling get to come into being, we should also legalize rape. If the "what if I were never born" argument is enough to override a woman's right to say no to childbirth, I don't see why it shouldn't be used to override a woman's right to say no to sexual intercourse. The ban on rape surely prevents many potential people from being born, since your average rapist will do it repeatedly if not caught. If Kiesling's biological father had been caught raping someone else first and thrown in prison prior to raping her mother, then Kiesling wouldn't exist, and clearly we can't have that. Well, at least we can't say it out loud, because that would be really impolite.