What is governments basic domestic duty? Enforce justice
It is a perversion of justice to violate another person as thoroughly as an abortion ban does. Two wrongs do not make a right. Justice cannot be enforced in this case. It isn't achievable. In the first place, the right thing to do is uknowable. Individuals have a responsibility to make decisions and live with the consequences. Creating an additional consequence in an attempt to force a choice you would prefer is abusing the power of the state and is wrong.
If enforcing justice is how you justify it, then it is unjustifiable, because there is no justice. All that changes is who the abused is.
I completely agree that the state has a vested interest and a duty to discourage the killing of one citizen by another. However, there is also an established precedent for when it is acceptable. Self-defense, from acts of aggression, including extortion, assault, most forms of abuse, we don't call it murder. And unfortunately, the government is incapable of distinguishing through legislation which babies are trying to kill which mothers and vice versa. When a thing can't be done, it shouldn't be done.
Justice cannot be served, the government is incapable in this instance even if it could be, and as terrible as it often is, it is not the place of government to participate in this decision one way or another. I'll join you at the bedside of the young woman who is afraid of the future and beg her not to end the life, but if she does, I'll defend her to my last from an oppressive government coming to imprison her for it.
No good comes from an abortion ban. Only pain. And the government that has the authority to force her to make the decision one way also has the power to force her to make it the other way. If you really care about this, understand that the ultimate vision of the authoritarian state is not a world where there are no abortions, but a world where it controls who gets to have a child.
If you really care about abortion, you will work to create a society in which women are not punished for having children. A world where no child is unwanted. A world where opportunity exists for everyone. Instead of judgment and condemnation for not having a child at the wrong time or with the wrong person, a world where motherhood forgives all past sins and earns you an honored position by default. It's impractical as hell and not something I'm working for, but right now the incentive to have an abortion for certain women is disgustingly high, and the very people most responsible for that are the ones trying to outlaw it.
If you can't see that such a ban is more about punishment than any real concern over the welfare of children, then it's because you aren't looking. Abortion may be terrible, but making it illegal is worse. It is worse morally, it is worse spiritually, it is worse economically, it is worse civilly. It is worse for men, worse for women, worse for children. Abortion being illegal is one of the worst ideas that has ever been tried, and one of the few where we have solid data to back that up. You can't reason your way out of it, individuals do the wrong thing all the time and there's no prison sentence for it, this is one of those things.
And as a big clue that it might be, a known pedo is likely to win an election because he supports it, despite his pedo-ness.
Being outraged that abortions are a thing is totally the right thing to be. The way to stop it is not through the power of the state. You could stop an abortion today, but I don't see you at the clinic offering cash for a baby. I don't see a bunch of unwanted kids that you've adopted. I haven't either. I'm not willing to do the actual hard work to de-incentivize abortion, I'm not going to go around accusing folks who are against the abusive coercion by the state of supporting murder because of it.
We stopped vigilante killing in a genuine pursuit of actual justice. And it took a monumental effort by all of society. For decades. Still working on it. Vast improvements in forensic science and civil and criminal procedure before the state began intervening in any meaningful way to prevent murder as you suggest. I submit for your consideration that the only reason murder is so rare has very little to do with it being illegal, and everything to do with there being other options for resolving conflicts and massive societal pressure discouraging the practice. I doubt very seriously if murder was legalized that you'd see a huge surge of it. Everyone's got family and vast swathes of society inherently understand that life is to be respected. The law doesn't keep us from violence, we are, universally,
making that choice.