Dred Scott apparently missed the memo on that. So did the southern states who cheered on the Supreme Court TRAMPLING "states rights" and FORCING northern states that did NOT allow slavery to comply with a slave owner's "right" to keep their slaves regardless of where the slave goes.
Firstly, both sides were willing to be quite hypocritical (Northern states arguing for states’ rights when it suited them and Southern states arguing for federal authority when it suited them) in order to get one over on their political opponents. Sound familiar?
As for Dred Scott, that obviously would not apply if it were an escaped slave from a foreign country.