Roe v Wade is a Supreme Court decision, right? That's not the same as the "law of the land."
If congress were to write legislation on the subject of abortion, the Supreme Court could rule on such a law in any way it sees fit. I understand a strong tendency of the Court to respect opinions of past Courts, but they don't have to, right?
The emphasis on Roe v Wade being the "law of the land" seems misplaced to me. But perhaps I'm missing something.
You are not missing anything, but to liberals Roe v. Wade is the Constitution. It can and it will be eventually overruled.