You have to work on both approaches at the same time. If we say that the decision should be left to each state then we are basically conceding that unborn children are not persons with a right to life. If we do that we have pretty much destroyed our argument for over-riding the mothers liberty interest in privacy and autonomy.
“You have to work on both approaches at the same time.”
I can agree with that. But I would suggest that unless you lead with the Frederalist approach, you will have no chance at all of getting the Constitutional Ammendment passed. Got to build the momentum from the current zero.