The right of self-defense is so deeply embedded in the psyches of the vast majority of citizens of both developed and developing nations that it is no surprise it is used to justify the legalization of abortion.The right of self-defense even to avoid bad things that might happen in the future, we should recall, was the justification for the start of the US's dubious "preventive war" against Iraq. I recall as if it were yesterday when I had NPR coverage on radio about three hours after the attack on the Trade Center the voice of a Catholic priest, before anything else, reminding the nationwide audience of the principle of self-defense, not only the right but the duty to protect ourselves from such attacks.
Very few people, however, will follow the sound logic of Hausotter in claiming that self-defense for abortion necessarily implies identifying the unborn as an "unjust aggressor." To even bring to mind the notion of an "unjust aggressor" at least is a backhanded acknowledgement that another person is involved and that the would-be victim might even have some duty to warn the aggressor to stop before the trigger is squeezed. Both legal and moral justification for abortion rights rests rather on total depersonalizing (or even perhaps the demonizing) of the unborn. Comparing the right to abortion to defending oneself against an attacking wild animal or a rampaging pit bull dog is probably more consistent with the way people would think about abortion if they bothered to go that deeply at all.
More telling about what specific right is claimed is the imperial and virtually unrestricted reign of personal rights over personal duties owed to others in post-modern Western cultures. The expansion of personal rights has not been counterbalanced by recognition and moral imperative to fulfill counterbalancing and corresponding duties. What prevails to some degree everywhere is a sense of entitlement to be completely unencumbered by anything that disrupts the hopes and dreams you have for your future. If you are alive and conscious in US today, you are entitled—or should be—to defend yourself against anyone or anything you judge to be threatening not just life itself but threatening to inconvenience the lifestyle you have become accustomed to, not to mention what may threaten your liberty and your pursuit of happiness.
This runs deep in the cultural fiber of Western societies and will remain so for many future generations.