1. All states recognize murder as a crime.
2. We do have many federal laws against murder. Check US Code Chapter 51. At that, section 1111 federally defines the classifications of murder (1st degree, 2nd degree and so on..) States are just the ones who enforce this in most cases but the law is federal.
Ambushing and killing night-time vandals would be regarded as First Degree Murder in some states, but could be considered laudable in Texas. Does that mean that Texas is delinquent in its protection of the vandals' right to live?
As a practical matter, I would posit that states have the authority to define "justifiable homicide" sufficiently loosely that an abortionist could almost always claim his actions qualified. Unless the Constitution is amended, I don't see any way of getting around that without also protecting the aforementioned vandals. Further, I think the remedy for abortion needs to be cultural rather than legal or political.