The problem with the original decision and the other rights cases that are vulnerable is that the privacy right they used really does not exist but rather than overturning them the cases should be affirmed on other grounds, namely the separation of church and state. Please see my direct comment to AP. You are correct on the states rights fallacy. If Congress were ever to pass a law codifying Roe, the Right would attack it as not within the enumerated powers of Congress. I would argue that it's within Congress's power under the Interstate Commerce Clause but I'm getting ahead of ourselves