Lets expand on this shall we...
First, lets combine the physical and the metaphysical. If you have a soul, it wouldn't be your hand, your feet, your penis, or even your brain directly. It would be your consciousness. Your ability to think, feel, and reasons, your hopes, and your fears, THAT would be your soul. If that isn't there, then you aren't there.
And, until pretty far, minimum 15 weeks in, a fetus is guaranteed to not have one. So, at that point, it isn't a person, it's just a cluster of cells. And to claim that terminating that is like saying that unplugging your brain dead relative on life support is murder as well even through it is a soulless husk with no person left in it.
Now, lets say you want to pivot and talk about the potential for consciousness later. Well, if that's the case, there is a 1 in near quintillion chance of an athletes foot infection to mutate a form of consciousness so its murder to spray that currently brain dead infection with tinactin. Or, lets be more realistic, science has already learned to take mature cells and revert them back into stem cells, and are getting to the point they can turn them into a fetus at which my the skin off my ass are as sacred as your living, breathing children are if you have them. Which is insane but that's the logic you end up with if you follow just potential.
So, it isn't about potential, its about what is. And the fetus has no soul because it has no consciousness at that point, so aborting it isn't murder, its dealing with a glorified vaginal infection before it turns into a person and becomes more.