As our law now stands (butchered by the left), it is a federal matter. It wasn’t in the beginning. Find me where the Constitution grants the earthly, legal definition of personhood to the federal government. The real definition is of course beyond our political structures. I think you know that.
The Constitution, as written, leaves everything not enumerated as a federal power to the states. Do you contest this?
The 14th amendment to the constitution contests this.