“I have a friend who has a Harvard Law Degree…” – I think Dr. Woods started this website so we could answer objections that started like that! Great to see liberty in action.
Regarding Brion’s response, with (2) I would be careful because your friend will simply retort, “No they did not have a legal claim and neither did the south. Thus, such an action was an implicit declaration of war.”
Also, I don’t see how Virginia did not have a legal right to secede if they ratified the Constitution (i.e. agreed to the contract that bound the Union of states) ONLY while explicitly retaining the right to leave the Union. I don’t see how Harvard Law degrees could change any of that. Perhaps your friend is reading strict modern contract law back into the 18th and 19th centuries?
Here’s another question you could ask (in addition to Brion’s list) that might get to the root of his bias:
(3) What would the history have to look like for you to recognize that Virginia [or any other state] did indeed have a legal right to secede?