Secondly, murder of a person has NEVER been legal anywhere in the United States.
First, let's look at your first point. Ben Carson actually spoke to this idea about a week ago and was ridiculed for it. He made a distinction between laws passed by a legislature and what he called 'judicial laws'. His opinion was that we actually were under no obligation to follow judicial law. The reality is that Roe v Wade truly is 'judicial law'. Abortion has NEVER been considered by our Congress. There has never been a vote. Abortion truly is judicially imposed law. Purely judicially imposed.
Your second point is that murder has never been legal anyplace in the US. That is true. One cannot take any life until a trial and conviction by a jury of peers for a capital offense.
A baby has obviously not committed a capital offense. An aborted baby has received no trial. It's death by abortion is, therefore, murder.
The only excuse would be that the baby is somehow not a human life. As you point out, it certainly isn't a giraffe.
If God gives the right to life -- and I believe He does -- then abortion is murder.
Andrew Jackson is purported to have said (his actual quote is far less flamboyant), "John Marshall has made his decision; now let him enforce it!" The Supreme Court has ZERO enforcement power.
All Congress has ever needed to do was pass a law acknowledging the obvious fact that preborn babies are persons and that would be the end of abortion. Any subsequent Congress would have an incredibly difficult job of repealing such legislation because they would be faced with the impossible task of explaining why a baby isn't a person.
Go to court with that argument. Single issue voters will guarantee a lib president