You can't even get yourself to say that the federal government SHOULD intervene when the state sanctions murder, thats what it is when you take somebodys life without informed consent or due process.
But the bigger point is that the federal government has the duty to protect unalienable rights and if you believe, like I do, that unborn babies are persons, then the federal government has the duty to protect their unalienable rights as well.
Staes can not violate the right to life, period.